Siegfried Glenzer
Professor of Photon Science and, by courtesy, of Mechanical Engineering
Photon Science Directorate
Bio
Siegfried Glenzer, who is the recipient of the recent E. O. Lawrence award, is Professor and High-Energy-Density division director at SLAC National Accelerator Laboratory. He joined SLAC as a distinguished scientist in 2013 to build a new discovery-class program in exploring matter in extreme conditions using high-power lasers and the world-class Linac Coherent Light Source x-ray beam. Before joining SLAC, he held the plasma physics group leader position at the Lawrence Livermore National Laboratory for 12 years, where he led the first inertial confinement fusion experiments on the National Ignition Facility. He has also been visiting lecturer at the University of California, Berkeley. Siegfried is the individual recipient of the American Physical Society “Excellence in Plasma Physics” Award (2003). He also won two DOE Excellence in Publications Awards (2011 & 2014) and two Science and Technology Awards (2005 & 2012). In 2004, he received the Alexander-von-Humboldt senior research prize and spent a research and teaching year at the Universität Rostock and at the Deutsche Elektronen Synchrotron in Hamburg, Germany. Since then, he has been the host for two Alexander-von-Humboldt Lynen postdoctoral fellows, two Lawrence postdoctoral fellows, three Peter-Paul-Ewald fellows, and has supervised more than 30 postdoctoral scientists both at LLNL and SLAC.
Siegfried authored and co-authored more than 400 journal publications. Siegfried published the textbook “Plasma Scattering of Electromagnetic Radiation” by D. H. Froula, S. H. Glenzer, N. C. Luhamn, Jr., J. Sheffield, 2nd edition (Elsevier, 2010) and is a fellow of the American Physical Society.
Academic Appointments
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Professor, Photon Science Directorate
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Professor (By courtesy), Mechanical Engineering
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Principal Investigator, Stanford PULSE Institute
Honors & Awards
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Dr. rer. nat. h. c., Rostock University (2019)
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E. O. Lawrence Award, US Department of Energy (2014)
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Humboldt Senior Research Prize, Alexander from Humboldt foundation (2004)
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Excellence in Plasma Physics Award, American Physical Society (2003)
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Fellow, American Physical Society (2001)
Boards, Advisory Committees, Professional Organizations
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Member, Advisory Committee of MIT's Center of Excellence HEDP Science (2018 - Present)
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Member, National Ignition Facility Discovery Science Technical Review Committee (2016 - Present)
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Member, INERTIAL CONFINEMENT FUSION IGNITION & HIGH YIELD (ICF) PROGRAM RED TEAM (ICF RED TEAM) (2017 - Present)
Current Research and Scholarly Interests
Please see our website for detailed information: https://heds.slac.stanford.edu
2024-25 Courses
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Independent Studies (6)
- Curricular Practical Training
PHYSICS 291 (Aut, Win, Spr, Sum) - Directed Studies in Applied Physics
APPPHYS 290 (Aut, Win, Spr, Sum) - Experimental Investigation of Engineering Problems
ME 392 (Aut, Win, Spr, Sum) - Independent Research and Study
PHYSICS 190 (Aut, Win, Spr, Sum) - Practical Training
ME 299B (Aut) - Research
PHYSICS 490 (Aut, Win, Spr, Sum)
- Curricular Practical Training
Stanford Advisees
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Doctoral Dissertation Reader (AC)
Derek Kuldinow -
Postdoctoral Faculty Sponsor
Maitrayee Ghosh, Alexis Marret, Eric Sung -
Doctoral Dissertation Advisor (AC)
Danielle Brown, Jhonnatan Gama Vazquez, Griffin Glenn, Claudia Parisuana, Edna Toro Garza
All Publications
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Diamond formation kinetics in shock-compressed C─H─O samples recorded by small-angle x-ray scattering and x-ray diffraction.
Science advances
2022; 8 (35): eabo0617
Abstract
Extreme conditions inside ice giants such as Uranus and Neptune can result in peculiar chemistry and structural transitions, e.g., the precipitation of diamonds or superionic water, as so far experimentally observed only for pure C─H and H2O systems, respectively. Here, we investigate a stoichiometric mixture of C and H2O by shock-compressing polyethylene terephthalate (PET) plastics and performing in situ x-ray probing. We observe diamond formation at pressures between 72 ± 7 and 125 ± 13 GPa at temperatures ranging from ~3500 to ~6000 K. Combining x-ray diffraction and small-angle x-ray scattering, we access the kinetics of this exotic reaction. The observed demixing of C and H2O suggests that diamond precipitation inside the ice giants is enhanced by oxygen, which can lead to isolated water and thus the formation of superionic structures relevant to the planets' magnetic fields. Moreover, our measurements indicate a way of producing nanodiamonds by simple laser-driven shock compression of cheap PET plastics.
View details for DOI 10.1126/sciadv.abo0617
View details for PubMedID 36054354
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The high-pressure lithium-palladium and lithium-palladium-hydrogen systems.
Scientific reports
2022; 12 (1): 12341
Abstract
The lithium-palladium and lithium-palladium-hydrogen systems are investigated at high pressures at and above room temperature. Two novel lithium-palladium compounds are found below [Formula: see text]. An ambient temperature phase is tentatively assigned as [Formula: see text], with [Formula: see text] Aat 8.64 GPa, isostructural with [Formula: see text]. The other phase occurs at high-temperature and is [Formula: see text], [Formula: see text] Aat 3.88 GPa and 200 [Formula: see text], similar to [Formula: see text], which is also known at high pressure. The presence of hydrogen in the system results in an [Formula: see text] structure with [Formula: see text] Aat 9.74 GPa. This persists up to [Formula: see text], the highest pressure studied. Below [Formula: see text] an fcc phase with a large unit cell, [Formula: see text] Aat 0.39 GPa, is also observed in the presence of hydrogen. On heating the hydrogen containing system at 4 GPa the [Formula: see text] phases persists to the melting point of lithium. In both systems melting the lithium results in the loss of crystalline diffraction from palladium containing phases. This is attributed to dissolution of the palladium in the molten lithium, and on cooling the palladium remains dispersed.
View details for DOI 10.1038/s41598-022-16694-2
View details for PubMedID 35853930
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Applicability of semiclassical methods for modeling laser-enhanced fusion rates in a realistic setting
PHYSICAL REVIEW C
2022; 105 (5)
View details for DOI 10.1103/PhysRevC.105.054001
View details for Web of Science ID 000810927800001
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Sub-micron thick liquid sheets produced by isotropically etched glass nozzles.
Lab on a chip
2022
Abstract
We report on the design and testing of glass nozzles used to produce liquid sheets. The sheet nozzles use a single converging channel chemically etched into glass wafers by standard lithographic methods. Operation in ambient air and vacuum was demonstrated. The measured sheet thickness ranges over one order of magnitude with the smallest thickness of 250 nm and the largest of 2.5 mum. Sheet thickness was shown to be independent of liquid flow rate, and dependent on the nozzle outlet area. Sheet surface roughness was dependent on nozzle surface finish and was on the order of 10 nm for polished nozzles. Electron transmission data is presented for various sheet thicknesses near the MeV mean free path and the charge pair distribution function for D2O is determined from electron scattering data.
View details for DOI 10.1039/d1lc00757b
View details for PubMedID 35234235
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Ultrafast visualization of incipient plasticity in dynamically compressed matter.
Nature communications
2022; 13 (1): 1055
Abstract
Plasticity is ubiquitous and plays a critical role in material deformation and damage; it inherently involves the atomistic length scale and picosecond time scale. A fundamental understanding of the elastic-plastic deformation transition, in particular, incipient plasticity, has been a grand challenge in high-pressure and high-strain-rate environments, impeded largely by experimental limitations on spatial and temporal resolution. Here, we report femtosecond MeV electron diffraction measurements visualizing the three-dimensional (3D) response of single-crystal aluminum to the ultrafast laser-induced compression. We capture lattice transitioning from a purely elastic to a plastically relaxed state within 5 ps, after reaching an elastic limit of~25 GPa. Our results allow the direct determination of dislocation nucleation and transport that constitute the underlying defect kinetics of incipient plasticity. Large-scale molecular dynamics simulations show good agreement with the experiment and provide an atomic-level description of the dislocation-mediated plasticity.
View details for DOI 10.1038/s41467-022-28684-z
View details for PubMedID 35217665
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Ultrafast structural response of shock-compressed plagioclase
METEORITICS & PLANETARY SCIENCE
2022
View details for DOI 10.1111/maps.13785
View details for Web of Science ID 000755921800001
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High Pressure Brillouin Spectroscopy and X-ray Diffraction of Cerium Dioxide
MATERIALS
2021; 14 (13)
Abstract
Simultaneous high-pressure Brillouin spectroscopy and powder X-ray diffraction of cerium dioxide powders are presented at room temperature to a pressure of 45 GPa. Micro- and nanocrystalline powders are studied and the density, acoustic velocities and elastic moduli determined. In contrast to recent reports of anomalous compressibility and strength in nanocrystalline cerium dioxide, the acoustic velocities are found to be insensitive to grain size and enhanced strength is not observed in nanocrystalline CeO2. Discrepancies in the bulk moduli derived from Brillouin and powder X-ray diffraction studies suggest that the properties of CeO2 are sensitive to the hydrostaticity of its environment. Our Brillouin data give the shear modulus, G0 = 63 (3) GPa, and adiabatic bulk modulus, KS0 = 142 (9) GPa, which is considerably lower than the isothermal bulk modulus, KT0∼ 230 GPa, determined by high-pressure X-ray diffraction experiments.
View details for DOI 10.3390/ma14133683
View details for Web of Science ID 000670971500001
View details for PubMedID 34279253
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Structure retrieval in liquid-phase electron scattering.
Physical chemistry chemical physics : PCCP
2020
Abstract
Electron scattering on liquid samples has been enabled recently by the development of ultrathin liquid sheet technologies. The data treatment of liquid-phase electron scattering has been mostly reliant on methodologies developed for gas electron diffraction, in which theoretical inputs and empirical fittings are often needed to account for the atomic form factor and remove the inelastic scattering background. In this work, we present an alternative data treatment method that is able to retrieve the radial distribution of all the charged particle pairs without the need of either theoretical inputs or empirical fittings. The merits of this new method are illustrated through the retrieval of real-space molecular structure from experimental electron scattering patterns of liquid water, carbon tetrachloride, chloroform, and dichloromethane.
View details for DOI 10.1039/d0cp06045c
View details for PubMedID 33367391
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Cryogenic Liquid Jets for High Repetition Rate Discovery Science.
Journal of visualized experiments : JoVE
2020
Abstract
This protocol presents a detailed procedure for the operation of continuous, micron-sized cryogenic cylindrical and planar liquid jets. When operated as described here, the jet exhibits high laminarity and stability for centimeters. Successful operation of a cryogenic liquid jet in the Rayleigh regime requires a basic understanding of fluid dynamics and thermodynamics at cryogenic temperatures. Theoretical calculations and typical empirical values are provided as a guide to design a comparable system. This report identifies the importance of both cleanliness during cryogenic source assembly and stability of the cryogenic source temperature once liquefied. The system can be used for high repetition rate laser-driven proton acceleration, with an envisioned application in proton therapy. Other applications include laboratory astrophysics, materials science, and next-generation particle accelerators.
View details for DOI 10.3791/61130
View details for PubMedID 32449743
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Femtosecond electronic structure response to high intensity XFEL pulses probed by iron X-ray emission spectroscopy.
Scientific reports
2020; 10 (1): 16837
Abstract
We report the time-resolved femtosecond evolution of the K-shell X-ray emission spectra of iron during high intensity illumination of X-rays in a micron-sized focused hard X-ray free electron laser (XFEL) beam. Detailed pulse length dependent measurements revealed that rapid spectral energy shift and broadening started within the first 10 fs of the X-ray illumination at intensity levels between 1017 and 1018 W cm-2. We attribute these spectral changes to the rapid evolution of high-density photoelectron mediated secondary collisional ionization processes upon the absorption of the incident XFEL radiation. These fast electronic processes, occurring at timescales well within the typical XFEL pulse durations (i.e., tens of fs), set the boundary conditions of the pulse intensity and sample parameters where the widely-accepted 'probe-before-destroy' measurement strategy can be adopted for electronic-structure related XFEL experiments.
View details for DOI 10.1038/s41598-020-74003-1
View details for PubMedID 33033373
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In situ X-ray diffraction of silicate liquids and glasses under dynamic and static compression to megabar pressures.
Proceedings of the National Academy of Sciences of the United States of America
2020
Abstract
Properties of liquid silicates under high-pressure and high-temperature conditions are critical for modeling the dynamics and solidification mechanisms of the magma ocean in the early Earth, as well as for constraining entrainment of melts in the mantle and in the present-day core-mantle boundary. Here we present in situ structural measurements by X-ray diffraction of selected amorphous silicates compressed statically in diamond anvil cells (up to 157 GPa at room temperature) or dynamically by laser-generated shock compression (up to 130 GPa and 6,000 K along the MgSiO3 glass Hugoniot). The X-ray diffraction patterns of silicate glasses and liquids reveal similar characteristics over a wide pressure and temperature range. Beyond the increase in Si coordination observed at 20 GPa, we find no evidence for major structural changes occurring in the silicate melts studied up to pressures and temperatures exceeding Earth's core mantle boundary conditions. This result is supported by molecular dynamics calculations. Our findings reinforce the widely used assumption that the silicate glasses studies are appropriate structural analogs for understanding the atomic arrangement of silicate liquids at these high pressures.
View details for DOI 10.1073/pnas.1920470117
View details for PubMedID 32414927
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High-Pressure Melt Curve and Phase Diagram of Lithium.
Physical review letters
2019; 123 (6): 065701
Abstract
We investigate the phase diagram of lithium at temperatures of 200 to 400 K, to pressures over 100 GPa using x-ray diffraction in diamond anvil cells, covering the region in which the melting curve is disputed. To overcome degradation of the diamond anvils by dense lithium we utilize a rapid compression scheme taking advantage of the high flux available at modern synchrotrons. Our results show the hR1 and cI16 phases to be stable to higher temperature than previously reported. The melting minima of lithium is found to be close to room temperature between 40 and 60 GPa, below which the solid is crystalline. Analysis of the stability fields of the cI16 and oC88 phases suggest the existence of a triple point between these and an undetermined solid phase at 60 GPa between 220 and 255 K.
View details for DOI 10.1103/PhysRevLett.123.065701
View details for PubMedID 31491150
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High-Pressure Melt Curve and Phase Diagram of Lithium
PHYSICAL REVIEW LETTERS
2019; 123 (6)
View details for DOI 10.1103/PhysRevLett.123.065701
View details for Web of Science ID 000479005200004
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Author Correction: Generation and characterization of ultrathin free-flowing liquid sheets.
Nature communications
2019; 10 (1): 1615
Abstract
The original version of this Article contained an error in Eq. (1). This has been corrected in both the PDF and HTML versions of the Article.
View details for DOI 10.1038/s41467-019-09457-7
View details for PubMedID 30944301
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Characterization of defect clusters in ion-irradiated tungsten by X-Ray diffuse scattering
JOURNAL OF NUCLEAR MATERIALS
2018; 510: 322–30
View details for DOI 10.1016/j.jnucmat.2018.07.062
View details for Web of Science ID 000446065100035
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Author Correction: Generation and characterization of ultrathin free-flowing liquid sheets.
Nature communications
2018; 9 (1): 2860
Abstract
The original version of this article omitted the following from the Acknowledgements:'P.B. was funded by the ELI Extreme Light Infrastructure Phase 2 (CZ.02.1.01/0.0/0.0/15008/0000162) from the European Regional Development Fund and the EUCALL project funded from the EU Horizon 2020 research and innovation programme under grant agreement No 654220,' which replaces the previous 'P.B. was funded by the ELI Extreme Light Infrastructure Phase 2 (CZ.02.1.01/0.0/0.0/15008/0000162) from the European Regional Development Fund.'This has been corrected in both the PDF and HTML versions of the article.
View details for DOI 10.1038/s41467-018-05365-4
View details for PubMedID 30018291
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Heterogeneous to homogeneous melting transition visualized with ultrafast electron diffraction.
Science (New York, N.Y.)
2018; 360 (6396): 1451–55
Abstract
The ultrafast laser excitation of matters leads to nonequilibrium states with complex solid-liquid phase-transition dynamics. We used electron diffraction at mega-electron volt energies to visualize the ultrafast melting of gold on the atomic scale length. For energy densities approaching the irreversible melting regime, we first observed heterogeneous melting on time scales of 100 to 1000 picoseconds, transitioning to homogeneous melting that occurs catastrophically within 10 to 20 picoseconds at higher energy densities. We showed evidence for the heterogeneous coexistence of solid and liquid. We determined the ion and electron temperature evolution and found superheated conditions. Our results constrain the electron-ion coupling rate, determine the Debye temperature, and reveal the melting sensitivity to nucleation seeds.
View details for DOI 10.1126/science.aar2058
View details for PubMedID 29954977
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Generation and characterization of ultrathin free-flowing liquid sheets
NATURE COMMUNICATIONS
2018; 9: 1353
Abstract
The physics and chemistry of liquid solutions play a central role in science, and our understanding of life on Earth. Unfortunately, key tools for interrogating aqueous systems, such as infrared and soft X-ray spectroscopy, cannot readily be applied because of strong absorption in water. Here we use gas-dynamic forces to generate free-flowing, sub-micron, liquid sheets which are two orders of magnitude thinner than anything previously reported. Optical, infrared, and X-ray spectroscopies are used to characterize the sheets, which are found to be tunable in thickness from over 1 μm down to less than 20 nm, which corresponds to fewer than 100 water molecules thick. At this thickness, aqueous sheets can readily transmit photons across the spectrum, leading to potentially transformative applications in infrared, X-ray, electron spectroscopies and beyond. The ultrathin sheets are stable for days in vacuum, and we demonstrate their use at free-electron laser and synchrotron light sources.
View details for DOI 10.1038/s41467-018-03696-w
View details for Web of Science ID 000429521200005
View details for PubMedID 29636445
View details for PubMedCentralID PMC5893585
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Call for papers: special issue on correlations in light-matter interactions
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
2017; 50 (9)
View details for DOI 10.1088/1361-6455/aa67d0
View details for Web of Science ID 000413309100001
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Relativistic Electron Streaming Instabilities Modulate Proton Beams Accelerated in Laser-Plasma Interactions
PHYSICAL REVIEW LETTERS
2017; 118 (19)
Abstract
We report experimental evidence that multi-MeV protons accelerated in relativistic laser-plasma interactions are modulated by strong filamentary electromagnetic fields. Modulations are observed when a preplasma is developed on the rear side of a μm-scale solid-density hydrogen target. Under such conditions, electromagnetic fields are amplified by the relativistic electron Weibel instability and are maximized at the critical density region of the target. The analysis of the spatial profile of the protons indicates the generation of B>10 MG and E>0.1 MV/μm fields with a μm-scale wavelength. These results are in good agreement with three-dimensional particle-in-cell simulations and analytical estimates, which further confirm that this process is dominant for different target materials provided that a preplasma is formed on the rear side with scale length ≳0.13λ_{0}sqrt[a_{0}]. These findings impose important constraints on the preplasma levels required for high-quality proton acceleration for multipurpose applications.
View details for DOI 10.1103/PhysRevLett.118.194801
View details for Web of Science ID 000401240300008
View details for PubMedID 28548516
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Relativistic Electron Streaming Instabilities Modulate Proton Beams Accelerated in Laser-Plasma Interactions
PHYSICAL REVIEW ACCELERATORS AND BEAMS
2017; 20 (5)
View details for DOI 10.1103/PhysRevLett.118.194801
View details for Web of Science ID 000401462400001
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Ab initio simulations of the dynamic ion structure factor of warm dense lithium
PHYSICAL REVIEW B
2017; 95 (14)
View details for DOI 10.1103/PhysRevB.95.144105
View details for Web of Science ID 000399382700002
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Calibration and characterization of a highly efficient spectrometer in von Hamos geometry for 7-10 keV x-rays
REVIEW OF SCIENTIFIC INSTRUMENTS
2017; 88 (4)
Abstract
We have built an absolutely calibrated, highly efficient, Bragg crystal spectrometer in von Hamos geometry. This zinc von Hamos spectrometer uses a crystal made from highly oriented pyrolytic graphite that is cylindrically bent along the non-dispersive axis. It is tuned to measure x-ray spectra in the 7-10 keV range and has been designed to be used on a Ten Inch Manipulator for the Omega and OmegaEP target chambers at the Laboratory for Laser Energetics in Rochester, USA. Significant shielding strategies and fluorescence mitigation have been implemented in addition to an imaging plate detector making it well suited for experiments in high-intensity environments. Here we present the design and absolute calibration as well as mosaicity and integrated reflectivity measurements.
View details for DOI 10.1063/1.4981793
View details for Web of Science ID 000400392800011
View details for PubMedID 28456236
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Observation of Betatron X-Ray Radiation in a Self-Modulated Laser Wakefield Accelerator Driven with Picosecond Laser Pulses
PHYSICAL REVIEW LETTERS
2017; 118 (13)
Abstract
We investigate a new regime for betatron x-ray emission that utilizes kilojoule-class picosecond lasers to drive wakes in plasmas. When such laser pulses with intensities of ∼5×10^{18} W/cm^{2} are focused into plasmas with electron densities of ∼1×10^{19} cm^{-3}, they undergo self-modulation and channeling, which accelerates electrons up to 200 MeV energies and causes those electrons to emit x rays. The measured x-ray spectra are fit with a synchrotron spectrum with a critical energy of 10-20 keV, and 2D particle-in-cell simulations were used to model the acceleration and radiation of the electrons in our experimental conditions.
View details for DOI 10.1103/PhysRevLett.118.134801
View details for Web of Science ID 000399152300008
View details for PubMedID 28409970
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A strong diffusive ion mode in dense ionized matter predicted by Langevin dynamics
NATURE COMMUNICATIONS
2017; 8
Abstract
The state and evolution of planets, brown dwarfs and neutron star crusts is determined by the properties of dense and compressed matter. Due to the inherent difficulties in modelling strongly coupled plasmas, however, current predictions of transport coefficients differ by orders of magnitude. Collective modes are a prominent feature, whose spectra may serve as an important tool to validate theoretical predictions for dense matter. With recent advances in free electron laser technology, X-rays with small enough bandwidth have become available, allowing the investigation of the low-frequency ion modes in dense matter. Here, we present numerical predictions for these ion modes and demonstrate significant changes to their strength and dispersion if dissipative processes are included by Langevin dynamics. Notably, a strong diffusive mode around zero frequency arises, which is not present, or much weaker, in standard simulations. Our results have profound consequences in the interpretation of transport coefficients in dense plasmas.
View details for DOI 10.1038/ncomms14125
View details for Web of Science ID 000392857900001
View details for PubMedID 28134338
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Using neutrons to measure keV temperatures in highly compressed plastic at multi-Gbar pressures
HIGH ENERGY DENSITY PHYSICS
2016; 21: 20-26
View details for DOI 10.1016/j.hedp.2016.10.001
View details for Web of Science ID 000389584700004
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Experimental room temperature hohlraum performance study on the National Ignition Facility
PHYSICS OF PLASMAS
2016; 23 (12)
View details for DOI 10.1063/1.4972548
View details for Web of Science ID 000392013000063
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A single-shot spatial chirp method for measuring initial AC conductivity evolution of femtosecond laser pulse excited warm dense matter
REVIEW OF SCIENTIFIC INSTRUMENTS
2016; 87 (11)
Abstract
To study the rapid evolution of AC conductivity from ultrafast laser excited warm dense matter (WDM), a spatial chirp single-shot method is developed utilizing a crossing angle pump-probe configuration. The pump beam is shaped individually in two spatial dimensions so that it can provide both sufficient laser intensity to excite the material to warm dense matter state and a uniform time window of up to 1 ps with sub-100 fs FWHM temporal resolution. Temporal evolution of AC conductivity in laser excited warm dense gold was also measured.
View details for DOI 10.1063/1.4962057
View details for Web of Science ID 000390242300263
View details for PubMedID 27910393
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The design of the optical Thomson scattering diagnostic for the National Ignition Facility
REVIEW OF SCIENTIFIC INSTRUMENTS
2016; 87 (11)
Abstract
The National Ignition Facility (NIF) is a 192 laser beam facility designed to support the Stockpile Stewardship, High Energy Density and Inertial Confinement Fusion (ICF) programs. We report on the design of an Optical Thomson Scattering (OTS) diagnostic that has the potential to transform the community's understanding of NIF hohlraum physics by providing first principle, local, time-resolved measurements of under-dense plasma conditions. The system design allows operation with different probe laser wavelengths by manual selection of the appropriate beam splitter and gratings before the shot. A deep-UV probe beam (λ0-210 nm) will be used to optimize the scattered signal for plasma densities of 5 × 1020electrons/cm3while a 3ω probe will be used for experiments investigating lower density plasmas of 1 × 1019electrons/cm3. We report the phase I design of a two phase design strategy. Phase I includes the OTS telescope, spectrometer, and streak camera; these will be used to assess the background levels at NIF. Phase II will include the design and installation of a probe laser.
View details for DOI 10.1063/1.4962043
View details for Web of Science ID 000390242300264
View details for PubMedID 27910656
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Simulated performance of the optical Thomson scattering diagnostic designed for the National Ignition Facility
REVIEW OF SCIENTIFIC INSTRUMENTS
2016; 87 (11)
Abstract
An optical Thomson scattering diagnostic has been designed for the National Ignition Facility to characterize under-dense plasmas. We report on the design of the system and the expected performance for different target configurations. The diagnostic is designed to spatially and temporally resolve the Thomson scattered light from laser driven targets. The diagnostic will collect scattered light from a 50 × 50 × 200 μm volume. The optical design allows operation with different probe laser wavelengths. A deep-UV probe beam (λ0= 210 nm) will be used to Thomson scatter from electron plasma densities of ∼5 × 1020cm-3while a 3ω probe will be used for plasma densities of ∼1 × 1019cm-3. The diagnostic package contains two spectrometers: the first to resolve Thomson scattering from ion acoustic wave fluctuations and the second to resolve scattering from electron plasma wave fluctuations. Expected signal levels relative to background will be presented for typical target configurations (hohlraums and a planar foil).
View details for DOI 10.1063/1.4959568
View details for Web of Science ID 000390242300225
View details for PubMedID 27910648
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High resolution x-ray Thomson scattering measurements from cryogenic hydrogen jets using the linac coherent light source
REVIEW OF SCIENTIFIC INSTRUMENTS
2016; 87 (11)
Abstract
We present the first spectrally resolved measurements of x-rays scattered from cryogenic hydrogen jets in the single photon counting limit. The 120 Hz capabilities of the LCLS, together with a novel hydrogen jet design [J. B. Kim et al., Rev. Sci. Instrum. (these proceedings)], allow for the ability to record a near background free spectrum. Such high-dynamic-range x-ray scattering measurements enable a platform to study ultra-fast, laser-driven, heating dynamics of hydrogen plasmas. This measurement has been achieved using two highly annealed pyrolytic graphite crystal spectrometers to spectrally resolve 5.5 keV x-rays elastically and inelastically scattered from cryogenic hydrogen and focused on Cornell-SLAC pixel array detectors [S. Herrmann et al., Nucl. Instrum. Methods Phys. Res., Sect. A 718, 550 (2013)].
View details for DOI 10.1063/1.4959792
View details for Web of Science ID 000390242300239
View details for PubMedID 27910564
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Measurement of high-dynamic range x-ray Thomson scattering spectra for the characterization of nano-plasmas at LCLS
REVIEW OF SCIENTIFIC INSTRUMENTS
2016; 87 (11)
Abstract
Atomic clusters can serve as ideal model systems for exploring ultrafast (∼100 fs) laser-driven ionization dynamics of dense matter on the nanometer scale. Resonant absorption of optical laser pulses enables heating to temperatures on the order of 1 keV at near solid density conditions. To date, direct probing of transient states of such nano-plasmas was limited to coherent x-ray imaging. Here we present the first measurement of spectrally resolved incoherent x-ray scattering from clusters, enabling measurements of transient temperature, densities, and ionization. Single shot x-ray Thomson scattering signals were recorded at 120 Hz using a crystal spectrometer in combination with a single-photon counting and energy-dispersive pnCCD. A precise pump laser collimation scheme enabled recording near background-free scattering spectra from Ar clusters with an unprecedented dynamic range of more than 3 orders of magnitude. Such measurements are important for understanding collective effects in laser-matter interactions on femtosecond time scales, opening new routes for the development of schemes for their ultrafast control.
View details for DOI 10.1063/1.4960502
View details for Web of Science ID 000390242300287
View details for PubMedID 27910491
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Development of a cryogenic hydrogen microjet for high-intensity, high-repetition rate experiments
REVIEW OF SCIENTIFIC INSTRUMENTS
2016; 87 (11)
Abstract
The advent of high-intensity, high-repetition-rate lasers has led to the need for replenishing targets of interest for high energy density sciences. We describe the design and characterization of a cryogenic microjet source, which can deliver a continuous stream of liquid hydrogen with a diameter of a few microns. The jet has been imaged at 1 μm resolution by shadowgraphy with a short pulse laser. The pointing stability has been measured at well below a mrad, for a stable free-standing filament of solid-density hydrogen.
View details for DOI 10.1063/1.4961089
View details for Web of Science ID 000390242300196
View details for PubMedID 27910321
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High-intensity laser-accelerated ion beam produced from cryogenic micro-jet target
REVIEW OF SCIENTIFIC INSTRUMENTS
2016; 87 (11)
Abstract
We report on the successful operation of a newly developed cryogenic jet target at high intensity laser-irradiation. Using the frequency-doubled Titan short pulse laser system at Jupiter Laser Facility, Lawrence Livermore National Laboratory, we demonstrate the generation of a pure proton beam a with maximum energy of 2 MeV. Furthermore, we record a quasi-monoenergetic peak at 1.1 MeV in the proton spectrum emitted in the laser forward direction suggesting an alternative acceleration mechanism. Using a solid-density mixed hydrogen-deuterium target, we are also able to produce pure proton-deuteron ion beams. With its high purity, limited size, near-critical density, and high-repetition rate capability, this target is promising for future applications.
View details for DOI 10.1063/1.4961270
View details for Web of Science ID 000390242300111
View details for PubMedID 27910336
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Single-shot mega-electronvolt ultrafast electron diffraction for structure dynamic studies of warm dense matter
REVIEW OF SCIENTIFIC INSTRUMENTS
2016; 87 (11)
Abstract
We have developed a single-shot mega-electronvolt ultrafast-electron-diffraction system to measure the structural dynamics of warm dense matter. The electron probe in this system is featured by a kinetic energy of 3.2 MeV and a total charge of 20 fC, with the FWHM pulse duration and spot size at sample of 350 fs and 120 μm respectively. We demonstrate its unique capability by visualizing the atomic structural changes of warm dense gold formed from a laser-excited 35-nm freestanding single-crystal gold foil. The temporal evolution of the Bragg peak intensity and of the liquid signal during solid-liquid phase transition are quantitatively determined. This experimental capability opens up an exciting opportunity to unravel the atomic dynamics of structural phase transitions in warm dense matter regime.
View details for DOI 10.1063/1.4960070
View details for Web of Science ID 000390242300094
View details for PubMedID 27910490
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Single-shot measurements of plasmons in compressed diamond with an x-ray laser (vol 22, 056319, 2015)
PHYSICS OF PLASMAS
2016; 23 (10)
View details for DOI 10.1063/1.4966204
View details for Web of Science ID 000387445500127
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Dual crystal x-ray spectrometer at 1.8 keV for high repetition-rate single-photon counting spectroscopy experiments
JOURNAL OF INSTRUMENTATION
2016; 11
View details for DOI 10.1088/1748-0221/11/08/P08015
View details for Web of Science ID 000387860100015
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X-ray scattering measurements on imploding CH spheres at the National Ignition Facility
PHYSICAL REVIEW E
2016; 94 (1)
View details for DOI 10.1103/PhysRevE.94.011202
View details for Web of Science ID 000380117600001
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Tracking the density evolution in counter-propagating shock waves using imaging X-ray scattering
APPLIED PHYSICS LETTERS
2016; 109 (3)
View details for DOI 10.1063/1.4959256
View details for Web of Science ID 000381385900008
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Absolute dosimetric characterization of Gafchromic EBT3 and HDv2 films using commercial flat-bed scanners and evaluation of the scanner response function variability.
Review of scientific instruments
2016; 87 (7): 073301-?
Abstract
Radiochromic films (RCF) are commonly used in dosimetry for a wide range of radiation sources (electrons, protons, and photons) for medical, industrial, and scientific applications. They are multi-layered, which includes plastic substrate layers and sensitive layers that incorporate a radiation-sensitive dye. Quantitative dose can be retrieved by digitizing the film, provided that a prior calibration exists. Here, to calibrate the newly developed EBT3 and HDv2 RCFs from Gafchromic™, we used the Stanford Medical LINAC to deposit in the films various doses of 10 MeV photons, and by scanning the films using three independent EPSON Precision 2450 scanners, three independent EPSON V750 scanners, and two independent EPSON 11000XL scanners. The films were scanned in separate RGB channels, as well as in black and white, and film orientation was varied. We found that the green channel of the RGB scan and the grayscale channel are in fact quite consistent over the different models of the scanner, although this comes at the cost of a reduction in sensitivity (by a factor ∼2.5 compared to the red channel). To allow any user to extend the absolute calibration reported here to any other scanner, we furthermore provide a calibration curve of the EPSON 2450 scanner based on absolutely calibrated, commercially available, optical density filters.
View details for DOI 10.1063/1.4954921
View details for PubMedID 27475550
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Calculation of Debye-Scherrer diffraction patterns from highly stressed polycrystalline materials
JOURNAL OF APPLIED PHYSICS
2016; 119 (21)
View details for DOI 10.1063/1.4953028
View details for Web of Science ID 000378923100056
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Matter under extreme conditions experiments at the Linac Coherent Light Source
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
2016; 49 (9)
View details for DOI 10.1088/0953-4075/49/9/092001
View details for Web of Science ID 000374698300001
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X-ray scattering measurements of dissociation-induced metallization of dynamically compressed deuterium
NATURE COMMUNICATIONS
2016; 7
Abstract
Hydrogen, the simplest element in the universe, has a surprisingly complex phase diagram. Because of applications to planetary science, inertial confinement fusion and fundamental physics, its high-pressure properties have been the subject of intense study over the past two decades. While sophisticated static experiments have probed hydrogen's structure at ever higher pressures, studies examining the higher-temperature regime using dynamic compression have mostly been limited to optical measurement techniques. Here we present spectrally resolved x-ray scattering measurements from plasmons in dynamically compressed deuterium. Combined with Compton scattering, and velocity interferometry to determine shock pressure and mass density, this allows us to extract ionization state as a function of compression. The onset of ionization occurs close in pressure to where density functional theory-molecular dynamics (DFT-MD) simulations show molecular dissociation, suggesting hydrogen transitions from a molecular and insulating fluid to a conducting state without passing through an intermediate atomic phase.
View details for DOI 10.1038/ncomms11189
View details for Web of Science ID 000374120600001
View details for PubMedID 27079420
View details for PubMedCentralID PMC4835540
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A direct-drive exploding-pusher implosion as the first step in development of a monoenergetic charged-particle backlighting platform at the National Ignition Facility
HIGH ENERGY DENSITY PHYSICS
2016; 18: 38-44
View details for DOI 10.1016/j.hedp.2016.01.001
View details for Web of Science ID 000370376100006
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Nanosecond formation of diamond and lonsdaleite by shock compression of graphite
NATURE COMMUNICATIONS
2016; 7
Abstract
The shock-induced transition from graphite to diamond has been of great scientific and technological interest since the discovery of microscopic diamonds in remnants of explosively driven graphite. Furthermore, shock synthesis of diamond and lonsdaleite, a speculative hexagonal carbon polymorph with unique hardness, is expected to happen during violent meteor impacts. Here, we show unprecedented in situ X-ray diffraction measurements of diamond formation on nanosecond timescales by shock compression of pyrolytic as well as polycrystalline graphite to pressures from 19 GPa up to 228 GPa. While we observe the transition to diamond starting at 50 GPa for both pyrolytic and polycrystalline graphite, we also record the direct formation of lonsdaleite above 170 GPa for pyrolytic samples only. Our experiment provides new insights into the processes of the shock-induced transition from graphite to diamond and uniquely resolves the dynamics that explain the main natural occurrence of the lonsdaleite crystal structure being close to meteor impact sites.
View details for DOI 10.1038/ncomms10970
View details for Web of Science ID 000372186800001
View details for PubMedID 26972122
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Resonance between heat-carrying electrons and Langmuir waves in inertial confinement fusion plasmas
PHYSICS OF PLASMAS
2016; 23 (1)
View details for DOI 10.1063/1.4939603
View details for Web of Science ID 000375853700040
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High-Energy Density science at the Linac Coherent Light Source
8TH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS (IFSA 2013)
2016; 688
View details for DOI 10.1088/1742-6596/688/1/012020
View details for Web of Science ID 000376159100020
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Hydrodynamic instabilities and mix studies on NIF: predictions, observations, and a path forward
8TH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS (IFSA 2013)
2016; 688
View details for DOI 10.1088/1742-6596/688/1/012090
View details for Web of Science ID 000376159100090
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Shock Hugoniot measurements of CH at Gbar pressures at the NIF
8TH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS (IFSA 2013)
2016; 688
View details for DOI 10.1088/1742-6596/688/1/012055
View details for Web of Science ID 000376159100055
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The preliminary design of the optical Thomson scattering diagnostic for the National Ignition Facility
9TH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS (IFSA 2015)
2016; 717
View details for DOI 10.1088/1742-6596/717/1/012089
View details for Web of Science ID 000387785300089
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Platform for spectrally resolved x-ray scattering from imploding capsules at the National Ignition Facility
9TH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS (IFSA 2015)
2016; 717
View details for DOI 10.1088/1742-6596/717/1/012067
View details for Web of Science ID 000387785300067
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Development of a WDM platform for charged-particle stopping experiments
9TH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS (IFSA 2015)
2016; 717
View details for DOI 10.1088/1742-6596/717/1/012118
View details for Web of Science ID 000387785300118
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Ultrafast electron kinetics in short pulse laser-driven dense hydrogen
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
2015; 48 (22)
View details for DOI 10.1088/0953-4075/48/22/224004
View details for Web of Science ID 000362459800005
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Free-Electron X-Ray Laser Measurements of Collisional-Damped Plasmons in Isochorically Heated Warm Dense Matter
PHYSICAL REVIEW LETTERS
2015; 115 (11)
Abstract
We present the first highly resolved measurements of the plasmon spectrum in an ultrafast heated solid. Multi-keV x-ray photons from the Linac Coherent Light Source have been focused to one micrometer diameter focal spots producing solid density aluminum plasmas with a known electron density of n_{e}=1.8×10^{23} cm^{-3}. Detailed balance is observed through the intensity ratio of up- and down-shifted plasmons in x-ray forward scattering spectra measuring the electron temperature. The plasmon damping is treated by electron-ion collision models beyond the Born approximation to determine the electrical conductivity of warm dense aluminum.
View details for DOI 10.1103/PhysRevLett.115.115001
View details for Web of Science ID 000360894300009
View details for PubMedID 26406836
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Ab initio calculation of the ion feature in x-ray Thomson scattering
PHYSICAL REVIEW E
2015; 92 (1)
Abstract
The spectrum of x-ray Thomson scattering is proportional to the dynamic structure factor. An important contribution is the ion feature which describes elastic scattering of x rays off electrons. We apply an ab initio method for the calculation of the form factor of bound electrons, the slope of the screening cloud of free electrons, and the ion-ion structure factor in warm dense beryllium. With the presented method we can calculate the ion feature from first principles. These results will facilitate a better understanding of x-ray scattering in warm dense matter and an accurate measurement of ion temperatures which would allow determining nonequilibrium conditions, e.g., along shock propagation.
View details for DOI 10.1103/PhysRevE.92.013103
View details for Web of Science ID 000357497800029
View details for PubMedID 26274290
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X-ray Thomson scattering diagnostics of impact ionization in laser-driven carbon foils
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
2015; 48 (12)
View details for DOI 10.1088/0953-4075/48/12/125701
View details for Web of Science ID 000354816600010
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Measurement of Charged-Particle Stopping in Warm Dense Plasma
PHYSICAL REVIEW LETTERS
2015; 114 (21)
Abstract
We measured the stopping of energetic protons in an isochorically heated solid-density Be plasma with an electron temperature of ∼32 eV, corresponding to moderately coupled [(e^{2}/a)/(k_{B}T_{e}+E_{F})∼0.3] and moderately degenerate [k_{B}T_{e}/E_{F}∼2] "warm-dense matter" (WDM) conditions. We present the first high-accuracy measurements of charged-particle energy loss through dense plasma, which shows an increased loss relative to cold matter, consistent with a reduced mean ionization potential. The data agree with stopping models based on an ad hoc treatment of free and bound electrons, as well as the average-atom local-density approximation; this work is the first test of these theories in WDM plasma.
View details for DOI 10.1103/PhysRevLett.114.215002
View details for Web of Science ID 000355101300013
View details for PubMedID 26066441
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Single-shot measurements of plasmons in compressed diamond with an x-ray laser
PHYSICS OF PLASMAS
2015; 22 (5)
View details for DOI 10.1063/1.4921407
View details for Web of Science ID 000355794300144
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The complex ion structure of warm dense carbon measured by spectrally resolved x-ray scattering
PHYSICS OF PLASMAS
2015; 22 (5)
View details for DOI 10.1063/1.4920943
View details for Web of Science ID 000355794300132
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Ultrabright X-ray laser scattering for dynamic warm dense matter physics
NATURE PHOTONICS
2015; 9 (4): 274-279
View details for DOI 10.1038/NPHOTON.2015.41
View details for Web of Science ID 000352083700017
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Observation of finite-wavelength screening in high-energy-density matter
NATURE COMMUNICATIONS
2015; 6
Abstract
A key component for the description of charged particle systems is the screening of the Coulomb interaction between charge carriers. First investigated in the 1920s by Debye and Hückel for electrolytes, charge screening is important for determining the structural and transport properties of matter as diverse as astrophysical and laboratory plasmas, nuclear matter such as quark-gluon plasmas, electrons in solids, planetary cores and charged macromolecules. For systems with negligible dynamics, screening is still mostly described using a Debye-Hückel-type approach. Here, we report the novel observation of a significant departure from the Debye-Hückel-type model in high-energy-density matter by probing laser-driven, shock-compressed plastic with high-energy X-rays. We use spectrally resolved X-ray scattering in a geometry that enables direct investigation of the screening cloud, and demonstrate that the observed elastic scattering amplitude is only well described within a more general approach.
View details for DOI 10.1038/ncomms7839
View details for Web of Science ID 000353703400006
View details for PubMedID 25904218
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Beyond the gain exponent: Effect of damping, scale length, and speckle length on stimulated scatter
PHYSICAL REVIEW E
2015; 91 (3)
Abstract
Three-dimensional wave propagation simulations and experiments show that the gain exponent, an often used metric to assess the likelihood of stimulated Brillouin scatter, is insufficient and must be augmented with another parameter, Nr, the ratio of the resonance length, Lres, to the laser speckle length. The damping rate of ion acoustic waves, ν, and thus Lres, which is proportional to ν, are easily varied with plasma species composition, e.g., by varying the ratio of hydrogen and carbon ions. As Nr decreases, stimulated Brillouin scattering increases despite the same gain exponent.
View details for DOI 10.1103/PhysRevE.91.031103
View details for Web of Science ID 000351433400002
View details for PubMedID 25871045
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Electron-ion temperature equilibration in warm dense tantalum
HIGH ENERGY DENSITY PHYSICS
2015; 14: 1-5
View details for DOI 10.1016/j.hedp.2014.10.003
View details for Web of Science ID 000353331800001
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Betatron radiation from laser plasma accelerators
LASER ACCELERATION OF ELECTRONS, PROTONS, AND IONS III; AND MEDICAL APPLICATIONS OF LASER-GENERATED BEAMS OF PARTICLES III
2015; 9514
View details for DOI 10.1117/12.2178685
View details for Web of Science ID 000357019800011
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Review of the National Ignition Campaign 2009-2012 (vol 21, 020501, 2014)
PHYSICS OF PLASMAS
2014; 21 (12)
View details for DOI 10.1063/1.4903459
View details for Web of Science ID 000347162700118
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Investigation of ion kinetic effects in direct-drive exploding-pusher implosions at the NIF
PHYSICS OF PLASMAS
2014; 21 (12)
View details for DOI 10.1063/1.4905064
View details for Web of Science ID 000347162700067
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New experimental platform to study high density laser-compressed matter
REVIEW OF SCIENTIFIC INSTRUMENTS
2014; 85 (11)
Abstract
We have developed a new experimental platform at the Linac Coherent Light Source (LCLS) which combines simultaneous angularly and spectrally resolved x-ray scattering measurements. This technique offers a new insights on the structural and thermodynamic properties of warm dense matter. The < 50 fs temporal duration of the x-ray pulse provides near instantaneous snapshots of the dynamics of the compression. We present a proof of principle experiment for this platform to characterize a shock-compressed plastic foil. We observe the disappearance of the plastic semi-crystal structure and the formation of a compressed liquid ion-ion correlation peak. The plasma parameters of shock-compressed plastic can be measured as well, but requires an averaging over a few tens of shots.
View details for DOI 10.1063/1.4896175
View details for Web of Science ID 000345646000203
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The effect of shock dynamics on compressibility of ignition-scale National Ignition Facility implosions
PHYSICS OF PLASMAS
2014; 21 (11)
View details for DOI 10.1063/1.4900621
View details for Web of Science ID 000345644200040
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New experimental platform to study high density laser-compressed matter.
Review of scientific instruments
2014; 85 (11): 11E616-?
Abstract
We have developed a new experimental platform at the Linac Coherent Light Source (LCLS) which combines simultaneous angularly and spectrally resolved x-ray scattering measurements. This technique offers a new insights on the structural and thermodynamic properties of warm dense matter. The < 50 fs temporal duration of the x-ray pulse provides near instantaneous snapshots of the dynamics of the compression. We present a proof of principle experiment for this platform to characterize a shock-compressed plastic foil. We observe the disappearance of the plastic semi-crystal structure and the formation of a compressed liquid ion-ion correlation peak. The plasma parameters of shock-compressed plastic can be measured as well, but requires an averaging over a few tens of shots.
View details for DOI 10.1063/1.4896175
View details for PubMedID 25430362
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Bent crystal spectrometer for both frequency and wavenumber resolved x-ray scattering at a seeded free-electron laser.
Review of scientific instruments
2014; 85 (9): 093106-?
Abstract
We present a cylindrically curved GaAs x-ray spectrometer with energy resolution ΔE/E = 1.1 × 10(-4) and wave-number resolution of Δk/k = 3 × 10(-3), allowing plasmon scattering at the resolution limits of the Linac Coherent Light Source (LCLS) x-ray free-electron laser. It spans scattering wavenumbers of 3.6 to 5.2/Å in 100 separate bins, with only 0.34% wavenumber blurring. The dispersion of 0.418 eV/13.5 μm agrees with predictions within 1.3%. The reflection homogeneity over the entire wavenumber range was measured and used to normalize the amplitude of scattering spectra. The proposed spectrometer is superior to a mosaic highly annealed pyrolytic graphite spectrometer when the energy resolution needs to be comparable to the LCLS seeded bandwidth of 1 eV and a significant range of wavenumbers must be covered in one exposure.
View details for DOI 10.1063/1.4894821
View details for PubMedID 25273706
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Bent crystal spectrometer for both frequency and wavenumber resolved x-ray scattering at a seeded free-electron laser
REVIEW OF SCIENTIFIC INSTRUMENTS
2014; 85 (9)
Abstract
We present a cylindrically curved GaAs x-ray spectrometer with energy resolution ΔE/E = 1.1 × 10(-4) and wave-number resolution of Δk/k = 3 × 10(-3), allowing plasmon scattering at the resolution limits of the Linac Coherent Light Source (LCLS) x-ray free-electron laser. It spans scattering wavenumbers of 3.6 to 5.2/Å in 100 separate bins, with only 0.34% wavenumber blurring. The dispersion of 0.418 eV/13.5 μm agrees with predictions within 1.3%. The reflection homogeneity over the entire wavenumber range was measured and used to normalize the amplitude of scattering spectra. The proposed spectrometer is superior to a mosaic highly annealed pyrolytic graphite spectrometer when the energy resolution needs to be comparable to the LCLS seeded bandwidth of 1 eV and a significant range of wavenumbers must be covered in one exposure.
View details for DOI 10.1063/1.4894821
View details for Web of Science ID 000342910500007
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Measuring the angular dependence of betatron x-ray spectra in a laser-wakefield accelerator
PLASMA PHYSICS AND CONTROLLED FUSION
2014; 56 (8)
View details for DOI 10.1088/0741-3335/56/8/084016
View details for Web of Science ID 000340055300017
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Progress in hohlraum physics for the National Ignition Facility
PHYSICS OF PLASMAS
2014; 21 (5)
View details for DOI 10.1063/1.4876966
View details for Web of Science ID 000337107200126
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Angular Dependence of Betatron X-Ray Spectra from a Laser-Wakefield Accelerator
PHYSICAL REVIEW LETTERS
2013; 111 (23)
Abstract
We present the first measurements of the angular dependence of the betatron x-ray spectrum produced by electrons inside the cavity of a laser-wakefield accelerator. Electrons accelerated up to 300 MeV energies produce a beam of broadband, forward-directed betatron x-ray radiation extending up to 80 keV. The angular resolved spectrum from an image plate-based spectrometer with differential filtering provides data in a single laser shot. The simultaneous spectral and spatial x-ray analysis allows for a three-dimensional reconstruction of electron trajectories with micrometer resolution, and we find that the angular dependence of the x-ray spectrum is showing strong evidence of anisotropic electron trajectories.
View details for DOI 10.1103/PhysRevLett.111.235004
View details for Web of Science ID 000328616300021
View details for PubMedID 24476282
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Plasmon measurements with a seeded x-ray laser
16th International Symposium on Laser-Aided Plasma Diagnostics
IOP PUBLISHING LTD. 2013
View details for DOI 10.1088/1748-0221/8/11/C11014
View details for Web of Science ID 000329193500014
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Raman Backscatter as a Remote Laser Power Sensor in High-Energy-Density Plasmas
PHYSICAL REVIEW LETTERS
2013; 111 (2)
Abstract
Stimulated Raman backscatter is used as a remote sensor to quantify the instantaneous laser power after transfer from outer to inner cones that cross in a National Ignition Facility (NIF) gas-filled hohlraum plasma. By matching stimulated Raman backscatter between a shot reducing outer versus a shot reducing inner power we infer that about half of the incident outer-cone power is transferred to inner cones, for the specific time and wavelength configuration studied. This is the first instantaneous nondisruptive measure of power transfer in an indirect drive NIF experiment using optical measurements.
View details for DOI 10.1103/PhysRevLett.111.025001
View details for Web of Science ID 000321752400021
View details for PubMedID 23889410
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NIF IGNITION CAMPAIGN TARGET PERFORMANCE AND REQUIREMENTS: STATUS MAY 2012
FUSION SCIENCE AND TECHNOLOGY
2013; 63 (2): 67-75
View details for Web of Science ID 000317709200003
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Observation of strong electromagnetic fields around laser-entrance holes of ignition-scale hohlraums in inertial-confinement fusion experiments at the National Ignition Facility
NEW JOURNAL OF PHYSICS
2013; 15
View details for DOI 10.1088/1367-2630/15/2/025040
View details for Web of Science ID 000315525500003
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X-Ray Scattering Measurements of Strong Ion-Ion Correlations in Shock-Compressed Aluminum
PHYSICAL REVIEW LETTERS
2013; 110 (6)
Abstract
The strong ion-ion correlation peak characteristic of warm dense matter (WDM) is observed for the first time using simultaneous angularly, temporally, and spectrally resolved x-ray scattering measurements in laser-driven shock-compressed aluminum. Laser-produced molybdenum x-ray line emission at an energy of 17.9 keV is employed to probe aluminum compressed to a density of ρ>8 g/cm(3). We observe a well pronounced peak in the static structure factor at a wave number of k=4.0 Å(-1). The measurements of the magnitude and position of this correlation peak are precise enough to test different theoretical models for the ion structure and show that only models taking the complex interaction in WDM into account agree with the data. This also demonstrates a new highly accurate diagnostic to directly measure the state of compression of warm dense matter.
View details for DOI 10.1103/PhysRevLett.110.065001
View details for Web of Science ID 000314687300019
View details for PubMedID 23432260
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Dynamics of exploding plasmas in a large magnetized plasma
PHYSICS OF PLASMAS
2013; 20 (1)
View details for DOI 10.1063/1.4773911
View details for Web of Science ID 000317286200010
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Probe Lasers for Characterizing High-temperature, High-density Plasmas
2013 CONFERENCE ON LASERS AND ELECTRO-OPTICS (CLEO)
2013
View details for Web of Science ID 000355262501086
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Towards an integrated model of the NIC layered implosions
IFSA 2011 - SEVENTH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS
2013; 59
View details for DOI 10.1051/epjconf/20135902009
View details for Web of Science ID 000342286400022
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Hohlraum designs for high velocity implosions on NIF
IFSA 2011 - SEVENTH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS
2013; 59
View details for DOI 10.1051/epjconf/20135902002
View details for Web of Science ID 000342286400015
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Shock timing on the National Ignition Facility: The first precision tuning series
IFSA 2011 - SEVENTH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS
2013; 59
View details for DOI 10.1051/epjconf/20135902005
View details for Web of Science ID 000342286400018
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Integrated thermodynamic model for ignition target performance
IFSA 2011 - SEVENTH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS
2013; 59
View details for DOI 10.1051/epjconf/20135904001
View details for Web of Science ID 000342286400049
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Reproducibility of hohlraum-driven implosion symmetry on the National Ignition Facility
IFSA 2011 - SEVENTH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS
2013; 59
View details for DOI 10.1051/epjconf/20135902010
View details for Web of Science ID 000342286400023
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Ignition tuning for the National Ignition Campaign
IFSA 2011 - SEVENTH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS
2013; 59
View details for DOI 10.1051/epjconf/20135901003
View details for Web of Science ID 000342286400003
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Symmetry tuning with megajoule laser pulses at the National Ignition Facility
IFSA 2011 - SEVENTH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS
2013; 59
View details for DOI 10.1051/epjconf/20135902007
View details for Web of Science ID 000342286400020
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Betatron x-ray production in mixed gases
LASER ACCELERATION OF ELECTRONS, PROTONS, AND IONS II; AND MEDICAL APPLICATIONS OF LASER-GENERATED BEAMS OF PARTICLES II; AND HARNESSING RELATIVISTIC PLASMA WAVES III
2013; 8779
View details for DOI 10.1117/12.2017187
View details for Web of Science ID 000323544600033
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Inelastic X-Ray Scattering from Shocked Liquid Deuterium
PHYSICAL REVIEW LETTERS
2012; 109 (26)
Abstract
The Fermi-degenerate plasma conditions created in liquid deuterium by a laser-ablation-driven shock wave were probed with noncollective, spectrally resolved, inelastic x-ray Thomson scattering employing Cl Ly(α) line emission at 2.96 keV. These first x-ray Thomson scattering measurements of the microscopic properties of shocked deuterium show an inferred spatially averaged electron temperature of 8±5 eV, an electron density of 2.2(±0.5)×10(23) cm(-3), and an ionization of 0.8 (-0.25, +0.15). Two-dimensional hydrodynamic simulations using equation-of-state models suited for the extreme parameters occurring in inertial confinement fusion research and planetary interiors are consistent with the experimental results.
View details for DOI 10.1103/PhysRevLett.109.265003
View details for Web of Science ID 000312934000007
View details for PubMedID 23368573
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Progress in the indirect-drive National Ignition Campaign
PLASMA PHYSICS AND CONTROLLED FUSION
2012; 54 (12)
View details for DOI 10.1088/0741-3335/54/12/124026
View details for Web of Science ID 000312579500029
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Implosion dynamics measurements at the National Ignition Facility
PHYSICS OF PLASMAS
2012; 19 (12)
View details for DOI 10.1063/1.4769268
View details for Web of Science ID 000312834000040
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Theory of x-ray scattering in high-pressure electrides
PHYSICAL REVIEW B
2012; 86 (17)
View details for DOI 10.1103/PhysRevB.86.174116
View details for Web of Science ID 000311693600001
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Observation of inhibited electron-ion coupling in strongly heated graphite
SCIENTIFIC REPORTS
2012; 2
Abstract
Creating non-equilibrium states of matter with highly unequal electron and lattice temperatures (T(ele)≠T(ion)) allows unsurpassed insight into the dynamic coupling between electrons and ions through time-resolved energy relaxation measurements. Recent studies on low-temperature laser-heated graphite suggest a complex energy exchange when compared to other materials. To avoid problems related to surface preparation, crystal quality and poor understanding of the energy deposition and transport mechanisms, we apply a different energy deposition mechanism, via laser-accelerated protons, to isochorically and non-radiatively heat macroscopic graphite samples up to temperatures close to the melting threshold. Using time-resolved x ray diffraction, we show clear evidence of a very small electron-ion energy transfer, yielding approximately three times longer relaxation times than previously reported. This is indicative of the existence of an energy transfer bottleneck in non-equilibrium warm dense matter.
View details for DOI 10.1038/srep00889
View details for Web of Science ID 000311708300001
View details for PubMedID 23189238
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Stochastic Ion Heating from Many Overlapping Laser Beams in Fusion Plasmas
PHYSICAL REVIEW LETTERS
2012; 109 (19)
Abstract
In this Letter, we show through numerical simulations and analytical results that overlapping multiple (N) laser beams in plasmas can lead to strong stochastic ion heating from many (~N(2)) electrostatic perturbations driven by beat waves between pairs of laser beams. For conditions typical of inertial-confinement-fusion experiment conditions, hundreds of such beat waves are driven in mm(3)-scale plasmas, leading to ion heating rates of several keV/ns. This mechanism saturates cross-beam energy transfer, with a reduction of linear gains by a factor ~4-5 and can strongly modify the overall hydrodynamics evolution of such laser-plasma systems.
View details for DOI 10.1103/PhysRevLett.109.195004
View details for Web of Science ID 000310853100011
View details for PubMedID 23215392
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Self-organized electromagnetic field structures in laser-produced counter-streaming plasmas
NATURE PHYSICS
2012; 8 (11): 809-812
View details for DOI 10.1038/NPHYS2434
View details for Web of Science ID 000310836700019
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Imaging of high-energy x-ray emission from cryogenic thermonuclear fuel implosions on the NIF
REVIEW OF SCIENTIFIC INSTRUMENTS
2012; 83 (10)
View details for DOI 10.1063/1.4733313
View details for Web of Science ID 000311562900123
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Diagnosing radiative shocks from deuterium and tritium implosions on NIF
REVIEW OF SCIENTIFIC INSTRUMENTS
2012; 83 (10)
Abstract
During the recent ignition tuning campaign at the National Ignition Facility, layered cryogenic deuterium and tritium capsules were imploded via x-ray driven ablation. The hardened gated x-ray imager diagnostic temporally and spatially resolves the x-ray emission from the core of the capsule implosion at energies above ~8 keV. On multiple implosions, ~200-400 ps after peak compression a spherically expanding radiative shock has been observed. This paper describes the methods used to characterize the radial profile and rate of expansion of the shock induced x-ray emission.
View details for DOI 10.1063/1.4729498
View details for Web of Science ID 000311562900204
View details for PubMedID 23127014
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Neutron spectrometry-An essential tool for diagnosing implosions at the National Ignition Facility (invited)
REVIEW OF SCIENTIFIC INSTRUMENTS
2012; 83 (10)
Abstract
DT neutron yield (Y(n)), ion temperature (T(i)), and down-scatter ratio (dsr) determined from measured neutron spectra are essential metrics for diagnosing the performance of inertial confinement fusion (ICF) implosions at the National Ignition Facility (NIF). A suite of neutron-time-of-flight (nTOF) spectrometers and a magnetic recoil spectrometer (MRS) have been implemented in different locations around the NIF target chamber, providing good implosion coverage and the complementarity required for reliable measurements of Y(n), T(i), and dsr. From the measured dsr value, an areal density (ρR) is determined through the relationship ρR(tot) (g∕cm(2)) = (20.4 ± 0.6) × dsr(10-12 MeV). The proportionality constant is determined considering implosion geometry, neutron attenuation, and energy range used for the dsr measurement. To ensure high accuracy in the measurements, a series of commissioning experiments using exploding pushers have been used for in situ calibration of the as-built spectrometers, which are now performing to the required accuracy. Recent data obtained with the MRS and nTOFs indicate that the implosion performance of cryogenically layered DT implosions, characterized by the experimental ignition threshold factor (ITFx), which is a function of dsr (or fuel ρR) and Y(n), has improved almost two orders of magnitude since the first shot in September, 2010.
View details for DOI 10.1063/1.4728095
View details for Web of Science ID 000311562900009
View details for PubMedID 23126835
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Simultaneous imaging electron- and ion-feature Thomson scattering measurements of radiatively heated Xe
REVIEW OF SCIENTIFIC INSTRUMENTS
2012; 83 (10)
Abstract
Uniform density and temperature Xe plasmas have been produced over >4 mm scale-lengths using x-rays generated in a cylindrical Pb cavity. The cavity is 750 μm in depth and diameter, and is heated by a 300 J, 2 ns square, 1054 nm laser pulse focused to a spot size of 200 μm at the cavity entrance. The plasma is characterized by simultaneous imaging Thomson scattering measurements from both the electron and ion scattering features. The electron feature measurement determines the spatial electron density and temperature profile, and using these parameters as constraints in the ion feature analysis allows an accurate determination of the charge state of the Xe ions. The Thomson scattering probe beam is 40 J, 200 ps, and 527 nm, and is focused to a 100 μm spot size at the entrance of the Pb cavity. Each system has a spatial resolution of 25 μm, a temporal resolution of 200 ps (as determined by the probe duration), and a spectral resolution of 2 nm for the electron feature system and 0.025 nm for the ion feature system. The experiment is performed in a Xe filled target chamber at a neutral pressure of 3-10 Torr, and the x-rays produced in the Pb ionize and heat the Xe to a charge state of 20±4 at up to 200 eV electron temperatures.
View details for DOI 10.1063/1.4740526
View details for Web of Science ID 000311562900195
View details for PubMedID 23127005
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Thomson scattering diagnostic for the measurement of ion species fraction
REVIEW OF SCIENTIFIC INSTRUMENTS
2012; 83 (10)
Abstract
Simultaneous Thomson scattering measurements of collective electron-plasma and ion-acoustic fluctuations have been utilized to determine ion species fraction from laser produced CH plasmas. The CH(2) foil is heated with 10 laser beams, 500 J per beam, at the Omega Laser facility. Thomson scattering measurements are made 4 mm from the foil surface using a 30 J 2ω probe laser with a 1 ns pulse length. Using a series of target shots the plasma evolution is measured from 2.5 ns to 9 ns after the rise of the heater beams. Measuring the electron density and temperature from the electron-plasma fluctuations constrains the fit of the two-ion species theoretical form factor for the ion feature such that the ion temperature, plasma flow velocity and ion species fraction are determined. The ion species fraction is determined to an accuracy of ±0.06 in species fraction.
View details for DOI 10.1063/1.4731007
View details for Web of Science ID 000311562900170
View details for PubMedID 23126981
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Measurement of electron temperature of imploded capsules at the National Ignition Facility
REVIEW OF SCIENTIFIC INSTRUMENTS
2012; 83 (10)
Abstract
The electron and ion temperatures of the imploded core plasma are two of the most important metrics of inertial confinement fusion experiments. We have developed a technique for inferring electron temperatures from the contrast of x-ray images observed through a group of x-ray filters. Generally, the plasma electron temperature exhibits spatial and temporal variations, so time-averaged and time-resolved measurements are expected to yield somewhat different results. By analyzing the intensity of images observed with both a time-integrated detector (imaging plates) and a time-resolved detector (gated micro-channel plate), we found the electron temperature observed from x-ray images to be systematically higher than the ion temperature inferred from fusion neutron spectroscopy.
View details for DOI 10.1063/1.4738660
View details for Web of Science ID 000311562900129
View details for PubMedID 23126943
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Measuring the absolute deuterium-tritium neutron yield using the magnetic recoil spectrometer at OMEGA and the NIF
REVIEW OF SCIENTIFIC INSTRUMENTS
2012; 83 (10)
View details for DOI 10.1063/1.4738657
View details for Web of Science ID 000311562900100
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Charged-particle spectroscopy for diagnosing shock rho R and strength in NIF implosions
REVIEW OF SCIENTIFIC INSTRUMENTS
2012; 83 (10)
View details for DOI 10.1063/1.4729672
View details for Web of Science ID 000311562900089
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Hard x-ray (> 100 keV) imager to measure hot electron preheat for indirectly driven capsule implosions on the NIF
REVIEW OF SCIENTIFIC INSTRUMENTS
2012; 83 (10)
View details for DOI 10.1063/1.4731742
View details for Web of Science ID 000311562900205
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Focal aberrations of large-aperture HOPG von-Hamos x-ray spectrometers
JOURNAL OF INSTRUMENTATION
2012; 7
View details for DOI 10.1088/1748-0221/7/09/P09015
View details for Web of Science ID 000309547100017
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Plasma switch as a temporal overlap tool for pump-probe experiments at FEL facilities
JOURNAL OF INSTRUMENTATION
2012; 7
View details for DOI 10.1088/1748-0221/7/08/P08007
View details for Web of Science ID 000308869800018
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Demonstration of a low electromagnetic pulse laser-driven argon gas jet x-ray source
APPLIED PHYSICS LETTERS
2012; 101 (2)
View details for DOI 10.1063/1.4734506
View details for Web of Science ID 000306360600105
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Assembly of High-Areal-Density Deuterium-Tritium Fuel from Indirectly Driven Cryogenic Implosions
PHYSICAL REVIEW LETTERS
2012; 108 (21)
Abstract
The National Ignition Facility has been used to compress deuterium-tritium to an average areal density of ~1.0±0.1 g cm(-2), which is 67% of the ignition requirement. These conditions were obtained using 192 laser beams with total energy of 1-1.6 MJ and peak power up to 420 TW to create a hohlraum drive with a shaped power profile, peaking at a soft x-ray radiation temperature of 275-300 eV. This pulse delivered a series of shocks that compressed a capsule containing cryogenic deuterium-tritium to a radius of 25-35 μm. Neutron images of the implosion were used to estimate a fuel density of 500-800 g cm(-3).
View details for DOI 10.1103/PhysRevLett.108.215005
View details for Web of Science ID 000304405000009
View details for PubMedID 23003274
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Precision Shock Tuning on the National Ignition Facility
PHYSICAL REVIEW LETTERS
2012; 108 (21)
Abstract
Ignition implosions on the National Ignition Facility [J. D. Lindl et al., Phys. Plasmas 11, 339 (2004)] are underway with the goal of compressing deuterium-tritium fuel to a sufficiently high areal density (ρR) to sustain a self-propagating burn wave required for fusion power gain greater than unity. These implosions are driven with a very carefully tailored sequence of four shock waves that must be timed to very high precision to keep the fuel entropy and adiabat low and ρR high. The first series of precision tuning experiments on the National Ignition Facility, which use optical diagnostics to directly measure the strength and timing of all four shocks inside a hohlraum-driven, cryogenic liquid-deuterium-filled capsule interior have now been performed. The results of these experiments are presented demonstrating a significant decrease in adiabat over previously untuned implosions. The impact of the improved shock timing is confirmed in related deuterium-tritium layered capsule implosions, which show the highest fuel compression (ρR~1.0 g/cm(2)) measured to date, exceeding the previous record [V. Goncharov et al., Phys. Rev. Lett. 104, 165001 (2010)] by more than a factor of 3. The experiments also clearly reveal an issue with the 4th shock velocity, which is observed to be 20% slower than predictions from numerical simulation.
View details for DOI 10.1103/PhysRevLett.108.215004
View details for Web of Science ID 000304405000008
View details for PubMedID 23003273
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Ultrafast Transitions from Solid to Liquid and Plasma States of Graphite Induced by X-Ray Free-Electron Laser Pulses
PHYSICAL REVIEW LETTERS
2012; 108 (21)
Abstract
We used photon pulses from an x-ray free-electron laser to study ultrafast x-ray-induced transitions of graphite from solid to liquid and plasma states. This was accomplished by isochoric heating of graphite samples and simultaneous probing via Bragg and diffuse scattering at high time resolution. We observe that disintegration of the crystal lattice and ion heating of up to 5 eV occur within tens of femtoseconds. The threshold fluence for Bragg-peak degradation is smaller and the ion-heating rate is faster than current x-ray-matter interaction models predict.
View details for DOI 10.1103/PhysRevLett.108.217402
View details for Web of Science ID 000304404700027
View details for PubMedID 23003301
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Dynamic structure factor in warm dense beryllium
NEW JOURNAL OF PHYSICS
2012; 14
View details for DOI 10.1088/1367-2630/14/5/055020
View details for Web of Science ID 000304875100003
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The velocity campaign for ignition on NIF
PHYSICS OF PLASMAS
2012; 19 (5)
View details for DOI 10.1063/1.3694840
View details for Web of Science ID 000304831100091
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Performance metrics for inertial confinement fusion implosions: Aspects of the technical framework for measuring progress in the National Ignition Campaign
PHYSICS OF PLASMAS
2012; 19 (5)
View details for DOI 10.1063/1.3696743
View details for Web of Science ID 000304831100102
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Characterizing counter-streaming interpenetrating plasmas relevant to astrophysical collisionless shocks
PHYSICS OF PLASMAS
2012; 19 (5)
View details for DOI 10.1063/1.3694124
View details for Web of Science ID 000304831100105
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Hot-spot mix in ignition-scale implosions on the NIF
PHYSICS OF PLASMAS
2012; 19 (5)
View details for DOI 10.1063/1.3694057
View details for Web of Science ID 000304831100093
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X-ray conversion efficiency in vacuum hohlraum experiments at the National Ignition Facility
PHYSICS OF PLASMAS
2012; 19 (5)
View details for DOI 10.1063/1.4704795
View details for Web of Science ID 000304831100038
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A high-resolution integrated model of the National Ignition Campaign cryogenic layered experiments
PHYSICS OF PLASMAS
2012; 19 (5)
View details for DOI 10.1063/1.4718595
View details for Web of Science ID 000304831100101
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Cryogenic thermonuclear fuel implosions on the National Ignition Facility
PHYSICS OF PLASMAS
2012; 19 (5)
View details for DOI 10.1063/1.4719686
View details for Web of Science ID 000304831100104
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Measurement of the Adiabatic Index in Be Compressed by Counterpropagating Shocks
PHYSICAL REVIEW LETTERS
2012; 108 (17)
View details for DOI 10.1103/PhysRevLett.108.175006
View details for Web of Science ID 000303196000002
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Measurement of Radiative Shock Properties by X-Ray Thomson Scattering
PHYSICAL REVIEW LETTERS
2012; 108 (14)
View details for DOI 10.1103/PhysRevLett.108.145001
View details for Web of Science ID 000302238900005
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Multistep redirection by cross-beam power transfer of ultrahigh-power lasers in a plasma
NATURE PHYSICS
2012; 8 (4): 344-349
View details for DOI 10.1038/NPHYS2239
View details for Web of Science ID 000302557600024
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First implosion experiments with cryogenic thermonuclear fuel on the National Ignition Facility
PLASMA PHYSICS AND CONTROLLED FUSION
2012; 54 (4)
View details for DOI 10.1088/0741-3335/54/4/045013
View details for Web of Science ID 000302122300013
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Adiabatic Index in Shock-Compressed Beryllium
CONTRIBUTIONS TO PLASMA PHYSICS
2012; 52 (3): 186-193
View details for DOI 10.1002/ctpp.201100101
View details for Web of Science ID 000302709500009
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Direct Measurement of Energetic Electrons Coupling to an Imploding Low-Adiabat Inertial Confinement Fusion Capsule
PHYSICAL REVIEW LETTERS
2012; 108 (13)
Abstract
We have imaged hard x-ray (>100 keV) bremsstrahlung emission from energetic electrons slowing in a plastic ablator shell during indirectly driven implosions at the National Ignition Facility. We measure 570 J in electrons with E>100 keV impinging on the fusion capsule under ignition drive conditions. This translates into an acceptable increase in the adiabat α, defined as the ratio of total deuterium-tritium fuel pressure to Fermi pressure, of 3.5%. The hard x-ray observables are consistent with detailed radiative-hydrodynamics simulations, including the sourcing and transport of these high energy electrons.
View details for DOI 10.1103/PhysRevLett.108.135006
View details for Web of Science ID 000302173000015
View details for PubMedID 22540711
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Self-consistent measurement of the equation of state of liquid deuterium
HIGH ENERGY DENSITY PHYSICS
2012; 8 (1): 76-80
View details for DOI 10.1016/j.hedp.2011.11.006
View details for Web of Science ID 000300130900013
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XUV spectroscopic characterization of warm dense aluminum plasmas generated by the free-electron-laser FLASH
LASER AND PARTICLE BEAMS
2012; 30 (1): 45-56
View details for DOI 10.1017/S026303461100067X
View details for Web of Science ID 000302371200007
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Studying astrophysical collisionless shocks with counterstreaming plasmas from high power lasers
HIGH ENERGY DENSITY PHYSICS
2012; 8 (1): 38-45
View details for DOI 10.1016/j.hedp.2011.11.001
View details for Web of Science ID 000300130900006
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An apparatus for the characterization of warm, dense deuterium with inelastic x-ray scattering
JOURNAL OF INSTRUMENTATION
2012; 7
View details for DOI 10.1088/1748-0221/7/02/P02004
View details for Web of Science ID 000303940900070
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Thomson Scattering Measurements of Temperature and Density in a Low-Density, Laser-Driven Magnetized Plasma
JOURNAL OF INSTRUMENTATION
2012; 7
View details for DOI 10.1088/1748-0221/7/02/P02002
View details for Web of Science ID 000303940900068
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GIGABAR MATERIAL PROPERTIES EXPERIMENTS ON NIF AND OMEGA
SHOCK COMPRESSION OF CONDENSED MATTER - 2011, PTS 1 AND 2
2012; 1426
View details for DOI 10.1063/1.3686321
View details for Web of Science ID 000302774300109
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X-ray Thomson Scattering Measurements from Shock-Compressed Deuterium
17TH INTERNATIONAL CONFERENCE ON ATOMIC PROCESSES IN PLASMAS (ICAPIP)
2012; 1438: 55-60
View details for DOI 10.1063/1.4707855
View details for Web of Science ID 000304804300008
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Diagnosing Implosions at the National Ignition Facility with X-Ray Spectroscopy
17TH INTERNATIONAL CONFERENCE ON ATOMIC PROCESSES IN PLASMAS (ICAPIP)
2012; 1438: 49-54
View details for DOI 10.1063/1.4707854
View details for Web of Science ID 000304804300007
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Measurements of the properties of highly compressed degenerate matter using x ray Thomson scattering
17TH INTERNATIONAL CONFERENCE ON ATOMIC PROCESSES IN PLASMAS (ICAPIP)
2012; 1438: 43-48
View details for DOI 10.1063/1.4707853
View details for Web of Science ID 000304804300006
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Warm Dense Aluminum Plasma generated by the Free-Electron-Laser FLASH
17TH INTERNATIONAL CONFERENCE ON ATOMIC PROCESSES IN PLASMAS (ICAPIP)
2012; 1438: 61-64
View details for DOI 10.1063/1.4707856
View details for Web of Science ID 000304804300009
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Development of X-ray Thomson scattering for implosion target characterization
HIGH ENERGY DENSITY PHYSICS
2011; 7 (4): 271-276
View details for DOI 10.1016/j.hedp.2011.05.013
View details for Web of Science ID 000298040400011
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A study of the contribution of doubly excited ionic states to the properties of hot dense high-Z plasmas
HIGH ENERGY DENSITY PHYSICS
2011; 7 (4): 371-376
View details for DOI 10.1016/j.hedp.2011.08.001
View details for Web of Science ID 000298040400025
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Stimulated forward Raman scattering in large scale-length laser-produced plasmas
JOURNAL OF INSTRUMENTATION
2011; 6
View details for DOI 10.1088/1748-0221/6/10/P10008
View details for Web of Science ID 000296819700013
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In-situ determination of dispersion and resolving power in simultaneous multiple-angle XUV spectroscopy
JOURNAL OF INSTRUMENTATION
2011; 6
View details for DOI 10.1088/1748-0221/6/10/P10001
View details for Web of Science ID 000296819700006
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Two-color Thomson scattering at FLASH
HIGH ENERGY DENSITY PHYSICS
2011; 7 (3): 145-149
View details for DOI 10.1016/j.hedp.2011.04.001
View details for Web of Science ID 000292700200006
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Progress towards ignition on the National Ignition Facility
NUCLEAR FUSION
2011; 51 (9)
View details for DOI 10.1088/0029-5515/51/9/094024
View details for Web of Science ID 000294731600025
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Ultraviolet Thomson scattering measurements of the electron and ion features with an energetic 263 nm probe
JOURNAL OF INSTRUMENTATION
2011; 6
View details for DOI 10.1088/1748-0221/6/08/P08004
View details for Web of Science ID 000294493700004
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Demonstration of a Narrow Energy Spread, similar to 0.5 GeV Electron Beam from a Two-Stage Laser Wakefield Accelerator
PHYSICAL REVIEW LETTERS
2011; 107 (4)
Abstract
Laser wakefield acceleration of electrons holds great promise for producing ultracompact stages of GeV scale, high-quality electron beams for applications such as x-ray free electron lasers and high-energy colliders. Ultrahigh intensity laser pulses can be self-guided by relativistic plasma waves (the wake) over tens of vacuum diffraction lengths, to give >1 GeV energy in centimeter-scale low density plasmas using ionization-induced injection to inject charge into the wake even at low densities. By restricting electron injection to a distinct short region, the injector stage, energetic electron beams (of the order of 100 MeV) with a relatively large energy spread are generated. Some of these electrons are then further accelerated by a second, longer accelerator stage, which increases their energy to ∼0.5 GeV while reducing the relative energy spread to <5% FWHM.
View details for DOI 10.1103/PhysRevLett.107.045001
View details for Web of Science ID 000292822700009
View details for PubMedID 21867013
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In-Flight Measurements of Capsule Shell Adiabats in Laser-Driven Implosions
PHYSICAL REVIEW LETTERS
2011; 107 (1)
Abstract
We present the first x-ray Thomson scattering measurements of temperature and density from spherically imploding matter. The shape of the Compton downscattered spectrum provides a first-principles measurement of the electron velocity distribution function, dependent on T(e) and the Fermi temperature T(F)∼n(e)(2/3). In-flight compressions of Be and CH targets reach 6-13 times solid density, with T(e)/T(F)∼0.4-0.7 and Γ(ii)∼5, resulting in minimum adiabats of ∼1.6-2. These measurements are consistent with low-entropy implosions and predictions by radiation-hydrodynamic modeling.
View details for DOI 10.1103/PhysRevLett.107.015002
View details for Web of Science ID 000292330900008
View details for PubMedID 21797548
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Fully relativistic form factor for Thomson scattering (vol 81, 036411, 2010)
PHYSICAL REVIEW E
2011; 83 (5)
View details for DOI 10.1103/PhysRevE.83.059905
View details for Web of Science ID 000290480100007
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Multi-beam effects on backscatter and its saturation in experiments with conditions relevant to ignition
PHYSICS OF PLASMAS
2011; 18 (5)
View details for DOI 10.1063/1.3587122
View details for Web of Science ID 000292209500121
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Diagnosing and controlling mix in National Ignition Facility implosion experiments
PHYSICS OF PLASMAS
2011; 18 (5)
View details for DOI 10.1063/1.3567520
View details for Web of Science ID 000292209500120
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Capsule implosion optimization during the indirect-drive National Ignition Campaign
PHYSICS OF PLASMAS
2011; 18 (5)
View details for DOI 10.1063/1.3592170
View details for Web of Science ID 000292209500006
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The experimental plan for cryogenic layered target implosions on the National Ignition Facility-The inertial confinement approach to fusion
PHYSICS OF PLASMAS
2011; 18 (5)
View details for DOI 10.1063/1.3592173
View details for Web of Science ID 000292209500007
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Symmetry tuning for ignition capsules via the symcap technique
PHYSICS OF PLASMAS
2011; 18 (5)
View details for DOI 10.1063/1.3574504
View details for Web of Science ID 000292209500117
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Analysis of the National Ignition Facility ignition hohlraum energetics experiments
PHYSICS OF PLASMAS
2011; 18 (5)
View details for DOI 10.1063/1.3562552
View details for Web of Science ID 000292209500112
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Point design targets, specifications, and requirements for the 2010 ignition campaign on the National Ignition Facility
PHYSICS OF PLASMAS
2011; 18 (5)
View details for DOI 10.1063/1.3592169
View details for Web of Science ID 000292209500005
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Three-wavelength scheme to optimize hohlraum coupling on the National Ignition Facility
PHYSICAL REVIEW E
2011; 83 (4)
Abstract
By using three tunable wavelengths on different cones of laser beams on the National Ignition Facility, numerical simulations show that the energy transfer between beams can be tuned to redistribute the energy within the cones of beams most prone to backscatter instabilities. These radiative hydrodynamics and laser-plasma interaction simulations have been tested against large-scale hohlraum experiments with two tunable wavelengths and reproduce the hohlraum energetics and symmetry. Using a third wavelength provides a greater level of control of the laser energy distribution and coupling in the hohlraum, and could significantly reduce stimulated Raman scattering losses and increase the hohlraum radiation drive while maintaining a good implosion symmetry.
View details for DOI 10.1103/PhysRevE.83.046409
View details for Web of Science ID 000290153000013
View details for PubMedID 21599318
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Demonstration of Ignition Radiation Temperatures in Indirect-Drive Inertial Confinement Fusion Hohlraums (vol 106, 085004, 2011)
PHYSICAL REVIEW LETTERS
2011; 106 (10)
View details for DOI 10.1103/PhysRevLett.106.109903
View details for Web of Science ID 000288163100011
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Characterization of a spherically bent quartz crystal for K alpha x-ray imaging of laser plasmas using a focusing monochromator geometry
JOURNAL OF INSTRUMENTATION
2011; 6
View details for DOI 10.1088/1748-0221/6/03/T03002
View details for Web of Science ID 000291342500011
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Demonstration of Ignition Radiation Temperatures in Indirect-Drive Inertial Confinement Fusion Hohlraums
PHYSICAL REVIEW LETTERS
2011; 106 (8)
Abstract
We demonstrate the hohlraum radiation temperature and symmetry required for ignition-scale inertial confinement fusion capsule implosions. Cryogenic gas-filled hohlraums with 2.2 mm-diameter capsules are heated with unprecedented laser energies of 1.2 MJ delivered by 192 ultraviolet laser beams on the National Ignition Facility. Laser backscatter measurements show that these hohlraums absorb 87% to 91% of the incident laser power resulting in peak radiation temperatures of T(RAD)=300 eV and a symmetric implosion to a 100 μm diameter hot core.
View details for DOI 10.1103/PhysRevLett.106.085004
View details for Web of Science ID 000287732600003
View details for PubMedID 21405580
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Observation of High Soft X-Ray Drive in Large-Scale Hohlraums at the National Ignition Facility
PHYSICAL REVIEW LETTERS
2011; 106 (8)
Abstract
The first soft x-ray radiation flux measurements from hohlraums using both a 96 and a 192 beam configuration at the National Ignition Facility have shown high x-ray conversion efficiencies of ∼85%-90%. These experiments employed gold vacuum hohlraums, 6.4 mm long and 3.55 mm in diameter, heated with laser energies between 150-635 kJ. The hohlraums reached radiation temperatures of up to 340 eV. These hohlraums for the first time reached coronal plasma conditions sufficient for two-electron processes and coronal heat conduction to be important for determining the radiation drive.
View details for DOI 10.1103/PhysRevLett.106.085003
View details for Web of Science ID 000287732600002
View details for PubMedID 21405579
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A diamond detector for X-ray bang-time measurement at the National Ignition Facility
JOURNAL OF INSTRUMENTATION
2011; 6
View details for DOI 10.1088/1748-0221/6/02/P02009
View details for Web of Science ID 000287860600015
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Ultrafast Melting of Carbon Induced by Intense Proton Beams
PHYSICAL REVIEW LETTERS
2010; 105 (26)
Abstract
Laser-produced proton beams have been used to achieve ultrafast volumetric heating of carbon samples at solid density. The isochoric melting of carbon was probed by a scattering of x rays from a secondary laser-produced plasma. From the scattering signal, we have deduced the fraction of the material that was melted by the inhomogeneous heating. The results are compared to different theoretical approaches for the equation of state which suggests modifications from standard models.
View details for DOI 10.1103/PhysRevLett.105.265701
View details for Web of Science ID 000286761900007
View details for PubMedID 21231678
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Thomson scattering on inhomogeneous targets
PHYSICAL REVIEW E
2010; 82 (5)
Abstract
The introduction of brilliant free-electron lasers enables new pump-probe experiments to characterize warm dense matter states. For instance, a short-pulse optical laser irradiates a liquid hydrogen jet that is subsequently probed with brilliant soft x-ray radiation. The strongly inhomogeneous plasma prepared by the optical laser is characterized with particle-in-cell simulations. The interaction of the soft x-ray probe radiation for different time delays between pump and probe with the inhomogeneous plasma is also taken into account via radiative hydrodynamic simulations. We calculate the respective scattering spectrum based on the Born-Mermin approximation for the dynamic structure factor considering the full density and temperature-dependent Thomson scattering cross section throughout the target. We can identify plasmon modes that are generated in different target regions and monitor their temporal evolution. Therefore, such pump-probe experiments are promising tools not only to measure the important plasma parameters density and temperature but also to gain valuable information about their time-dependent profile through the target. The method described here can be applied to various pump-probe scenarios by combining optical lasers and soft x ray, as well as x-ray sources.
View details for DOI 10.1103/PhysRevE.82.056404
View details for Web of Science ID 000283846000003
View details for PubMedID 21230599
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Probing near-solid density plasmas using soft x-ray scattering
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
2010; 43 (19)
View details for DOI 10.1088/0953-4075/43/19/194017
View details for Web of Science ID 000281958100018
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Hot electron measurements in ignition relevant Hohlraums on the National Ignition Facility
REVIEW OF SCIENTIFIC INSTRUMENTS
2010; 81 (10)
Abstract
On the National Ignition Facility (NIF), hot electrons generated in laser heated Hohlraums are inferred from the >20 keV bremsstrahlung emission measured with the time integrated FFLEX broadband spectrometer. New high energy (>200 keV) time resolved channels were added to infer the generated >170 keV hot electrons that can cause ignition capsule preheat. First hot electron measurements in near ignition scaled Hohlraums heated by 96-192 NIF laser beams are presented.
View details for DOI 10.1063/1.3478683
View details for Web of Science ID 000283754000158
View details for PubMedID 21033965
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Mapping the ionization state of laser-irradiated Ar gas jets with multiwavelength monochromatic x-ray imaging
REVIEW OF SCIENTIFIC INSTRUMENTS
2010; 81 (10)
Abstract
Two-dimensional monochromatic images of fast-electron stimulated Ar Kα and He-α x-ray self-emission have recorded a time-integrated map of the extent of Ar(≈6+) and Ar(16+) ions, respectively, within a high density (10(20) cm(-3) atomic density) Ar plasma. This plasma was produced by irradiating a 2 mm wide clustering Ar gas jet with an ultrahigh intensity (10(19) W/cm(2), 50 TW) Ti:sapphire laser operating at 800 nm. Spherically bent quartz crystals in the 200 (for Kα) and 201 (for He-α) planes were used as near-normal incidence reflective x-ray optics. We see that a large (830 μm long) region of plasma emits Kα primarily along the laser axis, while the He-α emission is confined to smaller hot spot (230 μm long) region that likely corresponds to the focal volume of the f/8 laser beam. X-ray spectra from a Bragg spectrometer operating in the von Hamos geometry indicate that the centroids of the Kα and He-α emission regions are separated by approximately 330 μm along the laser axis.
View details for DOI 10.1063/1.3491221
View details for Web of Science ID 000283754000253
View details for PubMedID 21034054
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Characterizing high energy spectra of NIF ignition Hohlraums using a differentially filtered high energy multipinhole x-ray imager
REVIEW OF SCIENTIFIC INSTRUMENTS
2010; 81 (10)
Abstract
Understanding hot electron distributions generated inside Hohlraums is important to the national ignition campaign for controlling implosion symmetry and sources of preheat. While direct imaging of hot electrons is difficult, their spatial distribution and spectrum can be deduced by detecting high energy x-rays generated as they interact with target materials. We used an array of 18 pinholes with four independent filter combinations to image entire Hohlraums with a magnification of 0.87× during the Hohlraum energetics campaign on NIF. Comparing our results with Hohlraum simulations indicates that the characteristic 10-40 keV hot electrons are mainly generated from backscattered laser-plasma interactions rather than from Hohlraum hydrodynamics.
View details for DOI 10.1063/1.3478682
View details for Web of Science ID 000283754000246
View details for PubMedID 21034047
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A scalable multipass laser cavity based on injection by frequency conversion for noncollective Thomson scattering
REVIEW OF SCIENTIFIC INSTRUMENTS
2010; 81 (10)
Abstract
A scalable setup using injection by frequency conversion to establish a multipassing cavity for noncollective Thomson scattering on low density plasmas is presented. The cavity is shown to support >10 passes through the target volume with a 400% increase in energy on target versus a single-pass setup. Rayleigh scattering experiments were performed and demonstrate the viability of the cell to study low density plasmas of the order of 10(12)-10(13) cm(-3). A high-repetition, low-energy, single-pass Thomson scattering setup was also performed on the University of California, Los Angeles Large Plasma Device and shows that the multipass cavity could have a significant advantage over the high-repetition approach due to the cavity setup's inherently higher signal per shot.
View details for DOI 10.1063/1.3460626
View details for Web of Science ID 000283754000056
View details for PubMedID 21033873
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Backscatter measurements for NIF ignition targets (invited)
REVIEW OF SCIENTIFIC INSTRUMENTS
2010; 81 (10)
Abstract
Backscattered light via laser-plasma instabilities has been measured in early NIF hohlraum experiments on two beam quads using a suite of detectors. A full aperture backscatter system and near backscatter imager (NBI) instrument separately measure the stimulated Brillouin and stimulated Raman scattered light. Both instruments work in conjunction to determine the total backscattered power to an accuracy of ∼15%. In order to achieve the power accuracy we have added time-resolution to the NBI for the first time. This capability provides a temporally resolved spatial image of the backscatter which can be viewed as a movie.
View details for DOI 10.1063/1.3491035
View details for Web of Science ID 000283754000141
View details for PubMedID 21033953
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Thomson-scattering measurements in the collective and noncollective regimes in laser produced plasmas (invited)
REVIEW OF SCIENTIFIC INSTRUMENTS
2010; 81 (10)
Abstract
We present simultaneous Thomson-scattering measurements of light scattered from ion-acoustic and electron-plasma fluctuations in a N(2) gas jet plasma. By varying the plasma density from 1.5×10(18) to 4.0×10(19) cm(-3) and the temperature from 100 to 600 eV, we observe the transition from the collective regime to the noncollective regime in the high-frequency Thomson-scattering spectrum. These measurements allow an accurate local measurement of fundamental plasma parameters: electron temperature, density, and ion temperature. Furthermore, experiments performed in the high densities typically found in laser produced plasmas result in scattering from electrons moving near the phase velocity of the relativistic plasma waves. Therefore, it is shown that even at low temperatures relativistic corrections to the scattered power must be included.
View details for DOI 10.1063/1.3478975
View details for Web of Science ID 000283754000061
View details for PubMedID 21033878
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Measuring symmetry of implosions in cryogenic Hohlraums at the NIF using gated x-ray detectors (invited)
REVIEW OF SCIENTIFIC INSTRUMENTS
2010; 81 (10)
Abstract
Ignition of imploding inertial confinement capsules requires, among other things, controlling the symmetry with high accuracy and fidelity. We have used gated x-ray imaging, with 10 μm and 70 ps resolution, to detect the x-ray emission from the imploded core of symmetry capsules at the National Ignition Facility. The measurements are used to characterize the time dependent symmetry and the x-ray bang time of the implosion from two orthogonal directions. These measurements were one of the primary diagnostics used to tune the parameters of the laser and Hohlraum to vary the symmetry and x-ray bang time of the implosion of cryogenically cooled ignition scale deuterium/helium filled plastic capsules. Here, we will report on the successful measurements performed with up to 1.2 MJ of laser energy in a fully integrated cryogenics gas-filled ignition-scale Hohlraum and capsule illuminated with 192 smoothed laser beams. We will describe the technique, the accuracy of the technique, and the results of the variation in symmetry with tuning parameters, and explain how that set was used to predictably tune the implosion symmetry as the laser energy, the laser cone wavelength separation, and the Hohlraum size were increased to ignition scales. We will also describe how to apply that technique to cryogenically layered tritium-hydrogen-deuterium capsules.
View details for DOI 10.1063/1.3481028
View details for Web of Science ID 000283754000213
View details for PubMedID 21034014
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4 omega Thomson scattering probe for high-density plasma characterization at Titan
REVIEW OF SCIENTIFIC INSTRUMENTS
2010; 81 (10)
Abstract
In preparation for the upcoming experiments on the Titan laser at the Jupiter Laser Facility, a new Thomson scattering system has been designed and implemented. This system allows electron temperature and density measurements in a high-density regime (n(e)>10(21) cm(-3)). A 263 nm probe has been demonstrated to produce a total energy of 15 J at 4ω(263 nm) in a 1 ns square pulse with a focal spot size of 100 μm. This probe has been used for imaging Thomson scattering of the ion feature. The goal of this study is to investigate the heating of a preformed plasma by a short-pulse heater beam.
View details for DOI 10.1063/1.3489136
View details for Web of Science ID 000283754000062
View details for PubMedID 21033879
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National Ignition Campaign Hohlraum energetics (vol 17, 056304, 2010)
PHYSICS OF PLASMAS
2010; 17 (10)
View details for DOI 10.1063/1.3484873
View details for Web of Science ID 000283772200098
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The first measurements of soft x-ray flux from ignition scale Hohlraums at the National Ignition Facility using DANTE (invited)
18th Topical Conference on High-Temperature Plasma Diagnostics
AMER INST PHYSICS. 2010
Abstract
The first 96 and 192 beam vacuum Hohlraum target experiments have been fielded at the National Ignition Facility demonstrating radiation temperatures up to 340 eV and fluxes of 20 TW/sr as viewed by DANTE representing an ∼20 times flux increase over NOVA/Omega scale Hohlraums. The vacuum Hohlraums were irradiated with 2 ns square laser pulses with energies between 150 and 635 kJ. They produced nearly Planckian spectra with about 30±10% more flux than predicted by the preshot radiation hydrodynamic simulations. To validate these results, careful verification of all component calibrations, cable deconvolution, and software analysis routines has been conducted. In addition, a half Hohlraum experiment was conducted using a single 2 ns long axial quad with an irradiance of ∼2×10(15) W/cm(2) for comparison with NIF Early Light experiments completed in 2004. We have also completed a conversion efficiency test using a 128-beam nearly uniformly illuminated gold sphere with intensities kept low (at 1×10(14) W/cm(2) over 5 ns) to avoid sensitivity to modeling uncertainties for nonlocal heat conduction and nonlinear absorption mechanisms, to compare with similar intensity, 3 ns OMEGA sphere results. The 2004 and 2009 NIF half-Hohlraums agreed to 10% in flux, but more importantly, the 2006 OMEGA Au Sphere, the 2009 NIF Au sphere, and the calculated Au conversion efficiency agree to ±5% in flux, which is estimated to be the absolute calibration accuracy of the DANTEs. Hence we conclude that the 30±10% higher than expected radiation fluxes from the 96 and 192 beam vacuum Hohlraums are attributable to differences in physics of the larger Hohlraums.
View details for DOI 10.1063/1.3491032
View details for Web of Science ID 000283754000218
View details for PubMedID 21034019
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Static ion structure factor for dense plasmas: Semi-classical and ab initio calculations
HIGH ENERGY DENSITY PHYSICS
2010; 6 (3): 305-310
View details for DOI 10.1016/j.hedp.2009.11.005
View details for Web of Science ID 000282654500003
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Self-Guided Laser Wakefield Acceleration beyond 1 GeV Using Ionization-Induced Injection
PHYSICAL REVIEW LETTERS
2010; 105 (10)
Abstract
The concepts of matched-beam, self-guided laser propagation and ionization-induced injection have been combined to accelerate electrons up to 1.45 GeV energy in a laser wakefield accelerator. From the spatial and spectral content of the laser light exiting the plasma, we infer that the 60 fs, 110 TW laser pulse is guided and excites a wake over the entire 1.3 cm length of the gas cell at densities below 1.5 × 10(18) cm(-3). High-energy electrons are observed only when small (3%) amounts of CO2 gas are added to the He gas. Computer simulations confirm that it is the K-shell electrons of oxygen that are ionized and injected into the wake and accelerated to beyond 1 GeV energy.
View details for DOI 10.1103/PhysRevLett.105.105003
View details for Web of Science ID 000281452000007
View details for PubMedID 20867526
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Plasmons in Strongly Coupled Shock-Compressed Matter
PHYSICAL REVIEW LETTERS
2010; 105 (7)
Abstract
We present the first measurements of the plasmon dispersion and damping in laser shock-compressed solid matter. Petawatt laser produced K-α radiation scatters on boron targets compressed by a 10 ns-long 400 J laser pulse. In the vicinity of the Fermi momentum, the scattering spectra show dispersionless, collisionally damped plasmons, indicating a strongly coupled electron liquid. These observations agree with calculations that include the Born-Mermin approximation to account for electron-ion collisional damping and local field corrections reflecting electron-electron correlations.
View details for DOI 10.1103/PhysRevLett.105.075003
View details for Web of Science ID 000280850600010
View details for PubMedID 20868053
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Imaging scattered x-ray radiation for measurement of local electron density in high-energy-density experiments
HIGH ENERGY DENSITY PHYSICS
2010; 6 (2): 194-199
View details for DOI 10.1016/j.hedp.2010.01.009
View details for Web of Science ID 000282614600013
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Electronic Structure of an XUV Photogenerated Solid-Density Aluminum Plasma
PHYSICAL REVIEW LETTERS
2010; 104 (22)
Abstract
By use of high intensity XUV radiation from the FLASH free-electron laser at DESY, we have created highly excited exotic states of matter in solid-density aluminum samples. The XUV intensity is sufficiently high to excite an inner-shell electron from a large fraction of the atoms in the focal region. We show that soft-x-ray emission spectroscopy measurements reveal the electronic temperature and density of this highly excited system immediately after the excitation pulse, with detailed calculations of the electronic structure, based on finite-temperature density functional theory, in good agreement with the experimental results.
View details for DOI 10.1103/PhysRevLett.104.225001
View details for Web of Science ID 000278207500016
View details for PubMedID 20867176
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Symmetry tuning via controlled crossed-beam energy transfer on the National Ignition Facility
PHYSICS OF PLASMAS
2010; 17 (5)
View details for DOI 10.1063/1.3325733
View details for Web of Science ID 000278182900118
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Laser wakefield acceleration at reduced density in the self-guided regime
PHYSICS OF PLASMAS
2010; 17 (5)
View details for DOI 10.1063/1.3323083
View details for Web of Science ID 000278182900141
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National Ignition Campaign Hohlraum energetics
PHYSICS OF PLASMAS
2010; 17 (5)
View details for DOI 10.1063/1.3354110
View details for Web of Science ID 000278182900117
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Capsule performance optimization in the National Ignition Campaign
PHYSICS OF PLASMAS
2010; 17 (5)
View details for DOI 10.1063/1.3298882
View details for Web of Science ID 000278182900114
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X-ray radiography and scattering diagnosis of dense shock-compressed matter
PHYSICS OF PLASMAS
2010; 17 (5)
View details for DOI 10.1063/1.3377785
View details for Web of Science ID 000278182900122
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Experimental basis for laser-plasma interactions in ignition hohlraums at the National Ignition Facility
PHYSICS OF PLASMAS
2010; 17 (5)
View details for DOI 10.1063/1.3304474
View details for Web of Science ID 000278182900115
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Observation of Ultrafast Nonequilibrium Collective Dynamics in Warm Dense Hydrogen
PHYSICAL REVIEW LETTERS
2010; 104 (12)
Abstract
We investigate ultrafast (fs) electron dynamics in a liquid hydrogen sample, isochorically and volumetrically heated to a moderately coupled plasma state. Thomson scattering measurements using 91.8 eV photons from the free-electron laser in Hamburg (FLASH at DESY) show that the hydrogen plasma has been driven to a nonthermal state with an electron temperature of 13 eV and an ion temperature below 0.1 eV, while the free-electron density is 2.8x10{20} cm{-3}. For dense plasmas, our experimental data strongly support a nonequilibrium kinetics model that uses impact ionization cross sections based on classical free-electron collisions.
View details for DOI 10.1103/PhysRevLett.104.125002
View details for Web of Science ID 000276072400024
View details for PubMedID 20366540
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Observation of Relativistic Effects in Collective Thomson Scattering
PHYSICAL REVIEW LETTERS
2010; 104 (10)
Abstract
We observe relativistic modifications to the Thomson scattering spectrum in a traditionally classical regime: v(osc)/c = eE(0)/cmomega(0) < 1 and T(e) < 1 keV. The modifications result from scattering off electron-plasma fluctuations with relativistic phase velocities. Normalized phase velocities v/c between 0.03 and 0.12 have been achieved in a N(2) gas-jet plasma by varying the plasma density from 3 x 10(18) cm(-3) to 7 x 10(19) cm(-3) and electron temperature between 85 and 700 eV. For these conditions, the complete temporally resolved Thomson scattering spectrum including the electron and ion features has been measured. A relativistic treatment of the Thomson scattering form factor shows excellent agreement with the experimental data.
View details for DOI 10.1103/PhysRevLett.104.105001
View details for Web of Science ID 000275543500029
View details for PubMedID 20366433
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Symmetric Inertial Confinement Fusion Implosions at Ultra-High Laser Energies
SCIENCE
2010; 327 (5970): 1228-1231
Abstract
Indirect-drive hohlraum experiments at the National Ignition Facility have demonstrated symmetric capsule implosions at unprecedented laser drive energies of 0.7 megajoule. One hundred and ninety-two simultaneously fired laser beams heat ignition-emulate hohlraums to radiation temperatures of 3.3 million kelvin, compressing 1.8-millimeter-diameter capsules by the soft x-rays produced by the hohlraum. Self-generated plasma optics gratings on either end of the hohlraum tune the laser power distribution in the hohlraum, which produces a symmetric x-ray drive as inferred from the shape of the capsule self-emission. These experiments indicate that the conditions are suitable for compressing deuterium-tritium-filled capsules, with the goal of achieving burning fusion plasmas and energy gain in the laboratory.
View details for DOI 10.1126/science.1185634
View details for Web of Science ID 000275162100031
View details for PubMedID 20110465
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Fully relativistic form factor for Thomson scattering
PHYSICAL REVIEW E
2010; 81 (3)
Abstract
We derive a fully relativistic form factor for Thomson scattering in unmagnetized plasmas valid to all orders in the normalized electron velocity, beta[over ]=v[over ]/c. The form factor is compared to a previously derived expression where the lowest order electron velocity, beta[over], corrections are included [J. Sheffield, (Academic Press, New York, 1975)]. The beta[over ] expansion approach is sufficient for electrostatic waves with small phase velocities such as ion-acoustic waves, but for electron-plasma waves the phase velocities can be near luminal. At high phase velocities, the electron motion acquires relativistic corrections including effective electron mass, relative motion of the electrons and electromagnetic wave, and polarization rotation. These relativistic corrections alter the scattered emission of thermal plasma waves, which manifest as changes in both the peak power and width of the observed Thomson-scattered spectra.
View details for DOI 10.1103/PhysRevE.81.036411
View details for Web of Science ID 000276199400086
View details for PubMedID 20365886
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Suprathermal electrons generated by the two-plasmon-decay instability in gas-filled Hohlraums
PHYSICS OF PLASMAS
2010; 17 (2)
View details for DOI 10.1063/1.3309481
View details for Web of Science ID 000275028700003
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X-ray Thomson Scattering Measurement in shock-compressed Beryllium
6th International Conference on Inertial Fusion Sciences and Applications
IOP PUBLISHING LTD. 2010
View details for DOI 10.1088/1742-6596/244/4/042015
View details for Web of Science ID 000285508000165
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Inferring the Electron Temperature and Density of Shocked Liquid Deuterium Using Inelastic X-Ray Scattering
SIXTH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS, PARTS 1-4
2010; 244
View details for DOI 10.1088/1742-6596/244/4/042017
View details for Web of Science ID 000285508000167
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Lasnex simulations of NIF vacuum hohlraum commissioning experiments
SIXTH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS, PARTS 1-4
2010; 244
View details for DOI 10.1088/1742-6596/244/3/032057
View details for Web of Science ID 000285508000146
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X-ray Thomson Scattering for measuring Dense Beryllium Plasma Collisionality
SIXTH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS, PARTS 1-4
2010; 244
View details for DOI 10.1088/1742-6596/244/3/032044
View details for Web of Science ID 000285508000133
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First hot electron measurements in near-ignition scale hohlraums on the National Ignition Facility
SIXTH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS, PARTS 1-4
2010; 244
View details for DOI 10.1088/1742-6596/244/2/022074
View details for Web of Science ID 000285508000084
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Transport of laser accelerated proton beams and isochoric heating of matter
SIXTH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS, PARTS 1-4
2010; 244
View details for DOI 10.1088/1742-6596/244/1/012009
View details for Web of Science ID 000285508000009
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Dense plasma X-ray scattering: Methods and applications
HIGH ENERGY DENSITY PHYSICS
2010; 6 (1): 1-8
View details for DOI 10.1016/j.hedp.2009.09.003
View details for Web of Science ID 000282614500001
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Soft X-ray scattering using FEL radiation for probing near-solid density plasmas at few electron volt temperatures
HIGH ENERGY DENSITY PHYSICS
2010; 6 (1): 15-20
View details for DOI 10.1016/j.hedp.2009.06.012
View details for Web of Science ID 000282614500003
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Measurements of Ionic Structure in Shock Compressed Lithium Hydride from Ultrafast X-Ray Thomson Scattering
PHYSICAL REVIEW LETTERS
2009; 103 (24)
Abstract
We present the first ultrafast temporally, spectrally, and angularly resolved x-ray scattering measurements from shock-compressed matter. The experimental spectra yield the absolute elastic and inelastic scattering intensities from the measured density of free electrons. Laser-compressed lithium-hydride samples are well characterized by inelastic Compton and plasmon scattering of a K-alpha x-ray probe providing independent measurements of temperature and density. The data show excellent agreement with the total intensity and structure when using the two-species form factor and accounting for the screening of ion-ion interactions.
View details for DOI 10.1103/PhysRevLett.103.245004
View details for Web of Science ID 000272627800020
View details for PubMedID 20366206
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Proton acceleration experiments and warm dense matter research using high power lasers
PLASMA PHYSICS AND CONTROLLED FUSION
2009; 51 (12)
View details for DOI 10.1088/0741-3335/51/12/124039
View details for Web of Science ID 000271940800050
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Evolution of elastic x-ray scattering in laser-shocked warm dense lithium
PHYSICAL REVIEW E
2009; 80 (6)
Abstract
We have studied the dynamics of warm dense Li with near-elastic x-ray scattering. Li foils were heated and compressed using shock waves driven by 4-ns-long laser pulses. Separate 1-ns-long laser pulses were used to generate a bright source of 2.96 keV Cl Ly- alpha photons for x-ray scattering, and the spectrum of scattered photons was recorded at a scattering angle of 120 degrees using a highly oriented pyrolytic graphite crystal operated in the von Hamos geometry. A variable delay between the heater and backlighter laser beams measured the scattering time evolution. Comparison with radiation-hydrodynamics simulations shows that the plasma is highly coupled during the first several nanoseconds, then relaxes to a moderate coupling state at later times. Near-elastic scattering amplitudes have been successfully simulated using the screened one-component plasma model. Our main finding is that the near-elastic scattering amplitudes are quite sensitive to the mean ionization state Z[over ] and by extension to the choice of ionization model in the radiation-hydrodynamics simulations used to predict plasma properties within the shocked Li.
View details for DOI 10.1103/PhysRevE.80.066406
View details for Web of Science ID 000273228000073
View details for PubMedID 20365285
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Isochoric heating of reduced mass targets by ultra-intense laser produced relativistic electrons
HIGH ENERGY DENSITY PHYSICS
2009; 5 (4): 244-248
View details for DOI 10.1016/j.hedp.2009.05.009
View details for Web of Science ID 000282614400003
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Measurements of the Critical Power for Self-Injection of Electrons in a Laser Wakefield Accelerator
PHYSICAL REVIEW LETTERS
2009; 103 (21)
Abstract
A laser wakefield acceleration study has been performed in the matched, self-guided, blowout regime producing 720 +/- 50 MeV quasimonoenergetic electrons with a divergence Deltatheta_{FWHM} of 2.85 +/- 0.15 mrad using a 10 J, 60 fs 0.8 microm laser. While maintaining a nearly constant plasma density (3 x 10{18} cm{-3}), the energy gain increased from 75 to 720 MeV when the plasma length was increased from 3 to 8 mm. Absolute charge measurements indicate that self-injection of electrons occurs when the laser power P exceeds 3 times the critical power P{cr} for relativistic self-focusing and saturates around 100 pC for P/P{cr} > 5. The results are compared with both analytical scalings and full 3D particle-in-cell simulations.
View details for DOI 10.1103/PhysRevLett.103.215006
View details for Web of Science ID 000272054300030
View details for PubMedID 20366048
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X-ray Thomson scattering in high energy density plasmas
REVIEWS OF MODERN PHYSICS
2009; 81 (4): 1625-1663
View details for DOI 10.1103/RevModPhys.81.1625
View details for Web of Science ID 000273229500006
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Temperature measurement through detailed balance in x-ray Thomson scattering
HIGH ENERGY DENSITY PHYSICS
2009; 5 (3): 182-186
View details for DOI 10.1016/j.hedp.2009.05.012
View details for Web of Science ID 000282413400011
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Turning solid aluminium transparent by intense soft X-ray photoionization
NATURE PHYSICS
2009; 5 (9): 693-696
View details for DOI 10.1038/NPHYS1341
View details for Web of Science ID 000270095600024
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Modelling, design and diagnostics for a photoionised plasma experiment
ASTROPHYSICS AND SPACE SCIENCE
2009; 322 (1-4): 117-121
View details for DOI 10.1007/s10509-008-9930-4
View details for Web of Science ID 000267293200020
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Observation of the Density Threshold Behavior for the Onset of Stimulated Raman Scattering in High-Temperature Hohlraum Plasmas
PHYSICAL REVIEW LETTERS
2009; 103 (4)
Abstract
We show that the measured stimulated Raman scattering (SRS) in a large-scale high-temperature plasma scales strongly with the plasma density, increasing by an order of magnitude when the electron density is increased by 20%. This is consistent with linear theory, including pump depletion, in a uniform plasma and, as the density is typically constrained by other processes, this effect will set a limit on drive laser beam intensity for forthcoming ignition experiments at the National Ignition Facility. Control of SRS at laser intensities consistent with 285 eV ignition hohlraums is achieved by using polarization smoothing which increases the intensity threshold for the onset of SRS by 1.6 +/- 0.2. These results were quantitatively predicted by full beam three-dimensional numerical laser-plasma interaction simulations.
View details for DOI 10.1103/PhysRevLett.103.045006
View details for Web of Science ID 000268307400036
View details for PubMedID 19659366
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Control of 2 omega (527 nm) stimulated Raman scattering in a steep density gradient plasma
PHYSICS OF PLASMAS
2009; 16 (6)
View details for DOI 10.1063/1.3143028
View details for Web of Science ID 000267599400036
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Ultrafast K alpha x-ray Thomson scattering from shock compressed lithium hydride
50th Annual Meeting of the Division of Plasma Physics of the American-Physical-Society
AMER INST PHYSICS. 2009
View details for DOI 10.1063/1.3099316
View details for Web of Science ID 000266500600121
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Frontiers of the physics of dense plasmas and planetary interiors: Experiments, theory, and applications
PHYSICS OF PLASMAS
2009; 16 (4)
View details for DOI 10.1063/1.3101818
View details for Web of Science ID 000266885800006
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Energy transfer between laser beams crossing in ignition hohlraums
PHYSICS OF PLASMAS
2009; 16 (4)
View details for DOI 10.1063/1.3103788
View details for Web of Science ID 000266885800052
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X-Ray Thomson-Scattering Measurements of Density and Temperature in Shock-Compressed Beryllium
PHYSICAL REVIEW LETTERS
2009; 102 (11)
Abstract
We present the first x-ray scattering measurements of the state of compression and heating in laser irradiated solid beryllium. The scattered spectra at two different angles show Compton and plasmon features indicating a dense Fermi-degenerate plasma state with a Fermi energy above 30 eV and with temperatures in the range of 10-15 eV. These measurements indicate compression by a factor of 3 in agreement with Hugoniot data and detailed radiation-hydrodynamic modeling.
View details for DOI 10.1103/PhysRevLett.102.115001
View details for Web of Science ID 000264380200033
View details for PubMedID 19392206
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Magnetically controlled plasma waveguide for laser wakefield acceleration
PLASMA PHYSICS AND CONTROLLED FUSION
2009; 51 (2)
View details for DOI 10.1088/0741-3335/51/2/024009
View details for Web of Science ID 000262585400010
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Tuning the Implosion Symmetry of ICF Targets via Controlled Crossed-Beam Energy Transfer
PHYSICAL REVIEW LETTERS
2009; 102 (2)
Abstract
Radiative hydrodynamics simulations of ignition experiments show that energy transfer between crossing laser beams allows tuning of the implosion symmetry. A new full-scale, three-dimensional quantitative model has been developed for crossed-beam energy transfer, allowing calculations of the propagation and coupling of multiple laser beams and their associated plasma waves in ignition hohlraums. This model has been implemented in a radiative-hydrodynamics code, demonstrating control of the implosion symmetry by a wavelength separation between cones of laser beams.
View details for DOI 10.1103/PhysRevLett.102.025004
View details for Web of Science ID 000262535900036
View details for PubMedID 19257284
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Magnetically Controlled Optical Plasma Waveguide for Electron Acceleration
ADVANCED ACCELERATOR CONCEPTS
2009; 1086: 165-?
View details for Web of Science ID 000264166500021
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K-alpha X-ray Thomson Scattering From Dense Plasmas
16th International Conference on Atomic Processes in Plasmas
AMER INST PHYSICS. 2009: 286–292
View details for Web of Science ID 000276195200038
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Soft X-Ray Thomson Scattering in Warm Dense Matter at FLASH
ULTRAFAST PHENOMENA XVI
2009; 92: 241-?
View details for Web of Science ID 000282108000078
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Study of x-ray radiation from a laser wakefield accelerator
ADVANCED ACCELERATOR CONCEPTS
2009; 1086: 235-?
View details for Web of Science ID 000264166500032
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Probing warm dense lithium by inelastic X-ray scattering
NATURE PHYSICS
2008; 4 (12): 940-944
View details for DOI 10.1038/nphys1103
View details for Web of Science ID 000261386000016
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Bremsstrahlung and line spectroscopy of warm dense aluminum plasma heated by xuv free-electron-laser radiation
PHYSICAL REVIEW E
2008; 78 (6)
Abstract
We report the creation of solid-density aluminum plasma using free-electron laser (FEL) radiation at 13.5nm wavelength. Ultrashort pulses were focused on a bulk Al target, yielding an intensity of 2x10;{14}Wcm;{2} . The radiation emitted from the plasma was measured using an xuv spectrometer. Bremsstrahlung and line intensity ratios yield consistent electron temperatures of about 38eV , supported by radiation hydrodynamics simulations. This shows that xuv FELs heat up plasmas volumetrically and homogeneously at warm-dense-matter conditions, which are accurately characterized by xuv spectroscopy.
View details for DOI 10.1103/PhysRevE.78.066406
View details for Web of Science ID 000262240600071
View details for PubMedID 19256961
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Probing the Hydrogen Melting Line at High Pressures by Dynamic Compression
PHYSICAL REVIEW LETTERS
2008; 101 (19)
Abstract
We investigate the capabilities of dynamic compression by intense heavy ion beams to yield information about the high pressure phases of hydrogen. Employing ab initio simulations and experimental data, a new wide range equation of state for hydrogen is constructed. The results show that the melting line up to its maximum as well as the transition from molecular fluids to fully ionized plasmas can be tested with the beam parameters soon to be available. We demonstrate that x-ray scattering can distinguish between phases and dissociation states.
View details for DOI 10.1103/PhysRevLett.101.194801
View details for Web of Science ID 000260776300032
View details for PubMedID 19113275
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Ultrafast x-ray Thomson scattering of shock-compressed matter
SCIENCE
2008; 322 (5898): 69-71
Abstract
Spectrally resolved scattering of ultrafast K-alpha x-rays has provided experimental validation of the modeling of the compression and heating of shocked matter. The elastic scattering component has characterized the evolution and coalescence of two shocks launched by a nanosecond laser pulse into lithium hydride with an unprecedented temporal resolution of 10 picoseconds. At shock coalescence, we observed rapid heating to temperatures of 25,000 kelvin when the scattering spectra show the collective plasmon oscillations that indicate the transition to the dense metallic plasma state. The plasmon frequency determines the material compression, which is found to be a factor of 3, thereby reaching conditions in the laboratory relevant for studying the physics of planetary formation.
View details for DOI 10.1126/science.1161466
View details for Web of Science ID 000259680200037
View details for PubMedID 18832640
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Demonstration of x-ray Thomson scattering using picosecond K-alpha x-ray sources in the characterization of dense heated matter
REVIEW OF SCIENTIFIC INSTRUMENTS
2008; 79 (10)
Abstract
We present K-alpha x-ray Thomson scattering from shock compressed matter for use as a diagnostic in determining the temperature, density, and ionization state with picosecond resolution. The development of this source as a diagnostic as well as stringent requirements for successful K-alpha x-ray Thomson scattering are addressed. Here, the first elastic and inelastic scattering measurements on a medium size laser facility have been observed. We present scattering data from solid density carbon plasmas with >1x10(5) photons in the elastic peak that validate the capability of single shot characterization of warm dense matter and the ability to use this scattering source at future free electron lasers and for fusion experiments at the National Ignition Facility (NIF), LLNL.
View details for DOI 10.1063/1.2965778
View details for Web of Science ID 000260573500158
View details for PubMedID 19044555
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Multicentimeter long high density magnetic plasmas for optical guiding
REVIEW OF SCIENTIFIC INSTRUMENTS
2008; 79 (10)
Abstract
We present a platform for producing long plasma channels suitable for guiding lasers over several centimeters by applying magnetic fields to limit the radial heat flux from a preforming laser beam. The resulting density gradient will be used as an optical plasma waveguide. The plasma conditions have been chosen to be consistent with the requirements for laser wakefield acceleration where multi-GeV electrons are predicted. A detailed description of the system used to produce the high (5 T) magnetic fields and initial results that show a 5 cm long plasma column are discussed.
View details for DOI 10.1063/1.2968711
View details for Web of Science ID 000260573500307
View details for PubMedID 19044692
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High order reflectivity of highly oriented pyrolytic graphite crystals for x-ray energies up to 22 keV
REVIEW OF SCIENTIFIC INSTRUMENTS
2008; 79 (10)
Abstract
We used Kr K alpha (12.6 keV), Zr K alpha (15.7 keV), and Ag K alpha (22.2 keV) x-rays, produced by petawatt-class laser pulses, to measure the integrated crystal reflectivity R(int) of flat highly oriented pyrolytic graphite (HOPG) up to the fifth order. The maximum R(int) was observed in first order (3.7 mrad at 12.6 keV), decreasing by a factor of 3-5 for every successive order, and dropping by a factor of 2-2.5 at 22.2 keV. The current study indicates that HOPG crystals are suitable for measuring scattering signals from high energy x-ray sources (E > or = 20 keV). These energies are required to penetrate through the high density plasma conditions encountered in inertial confinement fusion capsule implosions on the National Ignition Facility.
View details for DOI 10.1063/1.2966378
View details for Web of Science ID 000260573500069
View details for PubMedID 19044473
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A pulsed-laser calibration system for the laser backscatter diagnostics at the Omega laser
REVIEW OF SCIENTIFIC INSTRUMENTS
2008; 79 (10)
Abstract
A calibration system has been developed that allows a direct determination of the sensitivity of the laser backscatter diagnostics at the Omega laser. A motorized mirror at the target location redirects individual pulses of a millijoule-class laser onto the diagnostic to allow the in situ measurement of the local point response of the backscatter diagnostics. Featuring dual wavelength capability at the second and third harmonics of the Nd:YAG laser, both spectral channels of the backscatter diagnostics can be directly calibrated. In addition, channel cross-talk and polarization sensitivity can be determined. The calibration system has been employed repeatedly over the last two years and has enabled precise backscatter measurements of both stimulated Brillouin scattering and stimulated Raman scattering in gas-filled Hohlraum targets that emulate conditions relevant to those in inertial confinement fusion targets.
View details for DOI 10.1063/1.2953413
View details for Web of Science ID 000260573500305
View details for PubMedID 19044690
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Temporal dispersion of a spectrometer
REVIEW OF SCIENTIFIC INSTRUMENTS
2008; 79 (10)
Abstract
The temporal dispersion of an optical spectrometer has been characterized for a variety of conditions related to optical diagnostics to be fielded at the National Ignition Facility (e.g., full-aperture backscatter station, Thomson scattering). Significant time smear is introduced into these systems by the path length difference through the spectrometer. The temporal resolution is shown to depend only on the order of the grating, wavelength, and the number of grooves illuminated. To enhance the temporal resolution, the spectral gratings can be masked limiting the number of grooves illuminated. Experiments have been conducted to verify these calculations. The size and shape of masks are investigated and correlated with the exact shape of the temporal instrument function, which is required when interpreting temporally resolved data. The experiments used a 300 fs laser pulse and a picosecond optical streak camera to determine the temporal dispersion. This was done for multiple spectral orders, gratings, and optical masks.
View details for DOI 10.1063/1.2972022
View details for Web of Science ID 000260573500302
View details for PubMedID 19044687
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Optical transmission of glass for the National Ignition Facility near backscatter imagers under x-ray exposure
REVIEW OF SCIENTIFIC INSTRUMENTS
2008; 79 (10)
Abstract
In experiments at the National Ignition Facility (NIF), the near backscatter imager materials need to maintain high optical transmission while exposed to hohlraum generated x rays. Glass plates are incorporated in the design to protect the optical scattering plates from x-ray damage. Radiation environments spanning those expected on NIF have been produced at the Omega Laser Facility by symmetric laser illumination of 1 mm sized gold spheres. The time-dependent ultraviolet transmission of sample glass plates was measured. The data are interpreted with a free electron absorption model. Combined with the simulations of the hohlraum x-ray emission, this model is used to predict the transmission of the glass plates on the NIF. We predict that the plates should perform adequately up to the peak of the laser pulse.
View details for DOI 10.1063/1.2956833
View details for Web of Science ID 000260573500306
View details for PubMedID 19044691
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High contrast Kr gas jet K alpha x-ray source for high energy density physics experiments
REVIEW OF SCIENTIFIC INSTRUMENTS
2008; 79 (10)
Abstract
A high contrast 12.6 keV Kr K alpha source has been demonstrated on the petawatt-class Titan laser facility using strongly clustering Kr gas jet targets. The contrast ratio (K alpha to continuum) is 65, with a competitive ultrashort pulse laser to x-ray conversion efficiency of 10(-5). Filtered shadowgraphy indicates that the Kr K alpha and K beta x rays are emitted from a roughly 1x2 mm(2) emission volume, making this source suitable for area backlighting and scattering. Spectral calculations indicate a typical bulk electron temperature of 50-70 eV (i.e., mean ionization state 13-16), based on the observed ratio of K alpha to K beta. Kr gas jets provide a debris-free high energy K alpha source for time-resolved diagnosis of dense matter.
View details for DOI 10.1063/1.2955709
View details for Web of Science ID 000260573500175
View details for PubMedID 19044572
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Direct measurements of an increased threshold for stimulated Brillouin scattering with polarization smoothing in ignition hohlraum plasmas
PHYSICAL REVIEW LETTERS
2008; 101 (11)
Abstract
We demonstrate a significant reduction of stimulated Brillouin scattering by polarization smoothing in large-scale high-temperature hohlraum plasma conditions where filamentation is measured to be negligible. The stimulated Brillouin scattering experimental threshold (defined as the intensity at which 5% of the incident light is backscattered) is measured to increase by a factor of 1.7+/-0.2 when polarization smoothing is applied. An analytical model relevant to inertial confinement fusion plasma conditions shows that the measured reduction in backscatter with polarization smoothing results from the random spatial variation in polarization of the laser beam, not from the reduction in beam contrast.
View details for DOI 10.1103/PhysRevLett.101.115002
View details for Web of Science ID 000259188700024
View details for PubMedID 18851289
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Efficient multi-keV X-ray sources from laser-exploded metallic thin foils
PHYSICS OF PLASMAS
2008; 15 (9)
View details for DOI 10.1063/1.2973480
View details for Web of Science ID 000260031400037
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Plasmon resonance in warm dense matter
PHYSICAL REVIEW E
2008; 78 (2)
Abstract
Collective Thomson scattering with extreme ultraviolet light or x rays is shown to allow for a robust measurement of the free electron density in dense plasmas. Collective excitations like plasmons appear as maxima in the scattering signal. Their frequency position can directly be related to the free electron density. The range of applicability of the standard Gross-Bohm dispersion relation and of an improved dispersion relation in comparison to calculations based on the dielectric function in random phase approximation is investigated. More important, this well-established treatment of Thomson scattering on free electrons is generalized in the Born-Mermin approximation by including collisions. We show that, in the transition region from collective to noncollective scattering, the consideration of collisions is important.
View details for DOI 10.1103/PhysRevE.78.026411
View details for Web of Science ID 000259263700072
View details for PubMedID 18850950
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X-ray scattering measurements of radiative heating and cooling dynamics
PHYSICAL REVIEW LETTERS
2008; 101 (4)
Abstract
Spectrally and time-resolved x-ray scattering is used to extract the temperature and charge state evolution in a near solid density carbon foam driven by a supersonic soft x-ray heat wave. The measurements show a rapid heating of the foam material (approximately 200 eV/ns) followed by a similarly fast decline in the electron temperature as the foam cools. The results are compared to an analytic power balance model and to results from radiation-hydrodynamics simulations. Finally, the combination of charge state and temperature extracted from this known density isochorically heated plasma is used to distinguish between dense plasma ionization balance models.
View details for DOI 10.1103/PhysRevLett.101.045003
View details for Web of Science ID 000258427100028
View details for PubMedID 18764336
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X-ray conversion efficiency of high-Z hohlraum wall materials for indirect drive ignition
PHYSICS OF PLASMAS
2008; 15 (7)
View details for DOI 10.1063/1.2943700
View details for Web of Science ID 000258175800049
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Three-dimensional modeling of stimulated Brillouin scattering in ignition-scale experiments
PHYSICAL REVIEW LETTERS
2008; 100 (25)
Abstract
The first three-dimensional simulations of a high power 0.351 mum laser beam propagating through a high temperature hohlraum plasma are reported. We show that 3D fluid-based modeling of stimulated Brillouin scattering, including linear kinetic corrections, reproduces quantitatively the experimental measurements, provided it is coupled to detailed hydrodynamics simulation and a realistic description of the laser beam from its millimeter-size envelope down to the micron scale speckles. These simulations accurately predict the strong reduction of stimulated Brillouin scattering measured when polarization smoothing is used.
View details for DOI 10.1103/PhysRevLett.100.255001
View details for Web of Science ID 000257230500029
View details for PubMedID 18643667
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High K alpha x-ray conversion efficiency from extended source gas jet targets irradiated by ultra short laser pulses
APPLIED PHYSICS LETTERS
2008; 92 (24)
View details for DOI 10.1063/1.2945795
View details for Web of Science ID 000256934900024
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Energetics of multiple-ion species hohlraum plasmas
PHYSICS OF PLASMAS
2008; 15 (5)
View details for DOI 10.1063/1.2890126
View details for Web of Science ID 000256305200102
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Three-dimensional modeling of laser-plasma interaction: Benchmarking our predictive modeling tools versus experiments
PHYSICS OF PLASMAS
2008; 15 (5)
View details for DOI 10.1063/1.2844361
View details for Web of Science ID 000256305200108
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Suppression of stimulated Brillouin scattering by increased Landau damping in multiple-ion-species hohlraum plasmas
PHYSICAL REVIEW LETTERS
2008; 100 (10)
Abstract
We demonstrate that multiple-ion-species plasmas greatly reduce stimulated Brillouin scattering (SBS) in high-electron temperature inertial confinement fusion hohlraums. Landau damping is increased by adding hydrogen to a CO(2) gas filled hohlraum. We find that the SBS reflectivity decreases monotonically with increasing hydrogen fraction from 18% to 3% with a simultaneous increase of laser beam transmission. Detailed simulations with a 3D laser-plasma interaction code are in agreement with the experimentally observed reduction in backscattered light.
View details for DOI 10.1103/PhysRevLett.100.105001
View details for Web of Science ID 000254024500033
View details for PubMedID 18352195
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Green frequency-doubled laser-beam propagation in high-temperature hohlraum plasmas
PHYSICAL REVIEW LETTERS
2008; 100 (4)
Abstract
We demonstrate propagation and small backscatter losses of a frequency-doubled (2omega) laser beam interacting with inertial confinement fusion hohlraum plasmas. The electron temperature of 3.3 keV, approximately a factor of 2 higher than achieved in previous experiments with open geometry targets, approaches plasma conditions of high-fusion yield hohlraums. In this new temperature regime, we measure 2omega laser-beam transmission approaching 80% with simultaneous backscattering losses of less than 10%. These findings suggest that good laser coupling into fusion hohlraums using 2omega light is possible.
View details for DOI 10.1103/PhysRevLett.100.045002
View details for Web of Science ID 000252863400047
View details for PubMedID 18352288
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Pushing the limits of plasma length in inertial-fusion laser-plasma interaction experiments
PHYSICAL REVIEW LETTERS
2008; 100 (1)
Abstract
We demonstrate laser beam propagation and low backscatter in laser produced hohlraum plasmas of ignition plasma length. At intensities I < 5 x 10(14) W cm(-2) greater than 80% of the energy in a blue (3 omega, 351 nm) laser is transmitted through a L=5-mm long, high-temperature (Te = 2.5 keV), high-density (ne = 5 x 10(20) cm(-3)) plasma. These experiments show that the backscatter scales exponentially with plasma length which is consistent with linear theory. The backscatter calculated by a new steady state 3D laser-plasma interaction code developed for large ignition plasmas is in good agreement with the measurements.
View details for DOI 10.1103/PhysRevLett.100.015002
View details for Web of Science ID 000252285500035
View details for PubMedID 18232778
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Laser-plasma Interaction in Ignition Relevant Plasmas: benchmarking our 3D modelling capabilities versus recent experiments
5TH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS (IFSA2007)
2008; 112
View details for DOI 10.1088/1742-6596/112/2/022032
View details for Web of Science ID 000286312000049
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Hohlraum energetics and implosion symmetry with elliptical phase plates using a multi-cone beam geometry on OMEGA
5TH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS (IFSA2007)
2008; 112
View details for DOI 10.1088/1742-6596/112/2/022077
View details for Web of Science ID 000286312000094
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Compton scattering measurements from dense plasmas
5TH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS (IFSA2007)
2008; 112
View details for DOI 10.1088/1742-6596/112/3/032071
View details for Web of Science ID 000286312000187
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Target designs for energetics experiments on the National Ignition Facility
5TH INTERNATIONAL CONFERENCE ON INERTIAL FUSION SCIENCES AND APPLICATIONS (IFSA2007)
2008; 112
View details for DOI 10.1088/1742-6596/112/2/022022
View details for Web of Science ID 000286312000039
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Diagnosing direct-drive, shock-heated, and compressed plastic planar foils with noncollective spectrally resolved x-ray scattering
PHYSICS OF PLASMAS
2007; 14 (12)
View details for DOI 10.1063/1.2819675
View details for Web of Science ID 000251988200030
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Experiments and multiscale simulations of laser propagation through ignition-scale plasmas
NATURE PHYSICS
2007; 3 (10): 716-719
View details for DOI 10.1038/nphys709
View details for Web of Science ID 000249933900020
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Creation of hot dense matter in short-pulse laser-plasma interaction with tamped titanium foils
PHYSICS OF PLASMAS
2007; 14 (10)
View details for DOI 10.1063/1.2777118
View details for Web of Science ID 000250589700050
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The first target experiments on the national ignition facility
EUROPEAN PHYSICAL JOURNAL D
2007; 44 (2): 273-281
View details for DOI 10.1140/epjd/e2006-00111-6
View details for Web of Science ID 000248053800011
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Space-time characterization of laser plasma interactions in the warm dense matter regime
LASER AND PARTICLE BEAMS
2007; 25 (2): 239-244
View details for DOI 10.1017/S0263034607000067
View details for Web of Science ID 000247388500007
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Role of hydrodynamics simulations in laser-plasma interaction predictive capability
PHYSICS OF PLASMAS
2007; 14 (5)
View details for DOI 10.1063/1.2710782
View details for Web of Science ID 000246892900112
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K-alpha conversion efficiency measurements for X-ray scattering in inertial confinement fusion plasmas
HIGH ENERGY DENSITY PHYSICS
2007; 3 (1-2): 156-162
View details for DOI 10.1016/j.hedp.2007.02.012
View details for Web of Science ID 000208626000023
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Derivation of the static structure factor in strongly coupled non-equilibrium plasmas for X-ray scattering studies
HIGH ENERGY DENSITY PHYSICS
2007; 3 (1-2): 99-108
View details for DOI 10.1016/j.hedp.2007.02.006
View details for Web of Science ID 000208626000015
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Thomson scattering from near-solid density plasmas using soft X-ray free electron lasers
HIGH ENERGY DENSITY PHYSICS
2007; 3 (1-2): 120-130
View details for DOI 10.1016/j.hedp.2007.02.033
View details for Web of Science ID 000208626000018
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Proof of principle experiments that demonstrate utility of cocktail hohlraums for indirect drive ignition
PHYSICS OF PLASMAS
2007; 14 (5)
View details for DOI 10.1063/1.2712426
View details for Web of Science ID 000246892900119
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Laser beam propagation through inertial confinement fusion hohlraum plasmas
PHYSICS OF PLASMAS
2007; 14 (5)
View details for DOI 10.1063/1.2515054
View details for Web of Science ID 000246892900077
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Demonstration of enhanced radiation drive in hohlraums made from a mixture of high-Z wall materials
PHYSICAL REVIEW LETTERS
2007; 98 (17)
View details for DOI 10.1103/PhysRevLett.98.175003
View details for Web of Science ID 000246803900028
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Quenching of the nonlocal electron heat transport by large external magnetic fields in a laser-produced plasma measured with imaging thomson scattering
PHYSICAL REVIEW LETTERS
2007; 98 (13)
Abstract
We present a direct measurement of the quenching of nonlocal heat transport in a laser-produced plasma by applying large external magnetic fields (>10 T). The temporally resolved Thomson-scattering measurements of the electron temperature profile show that the heat front propagation transverse to a high-power laser beam is slowed resulting in extremely strong local heating. We find agreement with hydrodynamic modeling when including a magnetic field model that self-consistently evolves the fields in the plasma.
View details for DOI 10.1103/PhysRevLett.98.135001
View details for Web of Science ID 000245331500040
View details for PubMedID 17501207
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Ideal laser-beam propagation through high-temperature ignition hohlraum plasmas
PHYSICAL REVIEW LETTERS
2007; 98 (8)
Abstract
We demonstrate that a blue (3omega, 351 nm) laser beam with an intensity of 2 x 10(15) W cm(-2) propagates nearly within the original beam cone through a millimeter scale, T(e)=3.5 keV high density (n(e)=5 x 10(20) cm(-3)) plasma. The beam produced less than 1% total backscatter at these high temperatures and densities; the resulting transmission is greater than 90%. Scaling of the electron temperature in the plasma shows that the plasma becomes transparent for uniform electron temperatures above 3 keV. These results are consistent with linear theory thresholds for both filamentation and backscatter instabilities inferred from detailed hydrodynamic simulations. This provides a strong justification for current inertial confinement fusion designs to remain below these thresholds.
View details for DOI 10.1103/PhysRevLett.98.085001
View details for Web of Science ID 000244420700034
View details for PubMedID 17359104
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Observations of plasmons in warm dense matter
PHYSICAL REVIEW LETTERS
2007; 98 (6)
Abstract
We present the first collective x-ray scattering measurements of plasmons in solid-density plasmas. The forward scattering spectra of a laser-produced narrow-band x-ray line from isochorically heated beryllium show that the plasmon frequency is a sensitive measure of the electron density. Dynamic structure calculations that include collisions and detailed balance match the measured plasmon spectrum indicating that this technique will enable new applications to determine the equation of state and compressibility of dense matter.
View details for DOI 10.1103/PhysRevLett.98.065002
View details for Web of Science ID 000244117400036
View details for PubMedID 17358952
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Hypernetted chain calculations for two-component plasmas
CONTRIBUTIONS TO PLASMA PHYSICS
2007; 47 (4-5): 324-330
View details for DOI 10.1002/ctpp.200710043
View details for Web of Science ID 000248074200016
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X-ray Thomson scattering from dense Plasmas
ATOMIC PROCESSES IN PLASMAS
2007; 926: 8-17
View details for Web of Science ID 000249095400003
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Shift of ClK alpha and K-beta lines in laser produced dense plasmas
CONTRIBUTIONS TO PLASMA PHYSICS
2007; 47 (4-5): 309-314
View details for DOI 10.1002/ctpp.200710041
View details for Web of Science ID 000248074200014
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High magnetic field generation for laser-plasma experiments
REVIEW OF SCIENTIFIC INSTRUMENTS
2006; 77 (11)
View details for DOI 10.1063/1.2356854
View details for Web of Science ID 000242408600028
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Implementation of imaging Thomson scattering on the Omega Laser
REVIEW OF SCIENTIFIC INSTRUMENTS
2006; 77 (10)
View details for DOI 10.1063/1.2220077
View details for Web of Science ID 000241722800094
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Qualification of a near backscattering imaging system on the National Ignition Facility
REVIEW OF SCIENTIFIC INSTRUMENTS
2006; 77 (10)
View details for DOI 10.1063/1.2336466
View details for Web of Science ID 000241722800103
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Solid-density plasma characterization with x-ray scattering on the 200 J Janus laser
REVIEW OF SCIENTIFIC INSTRUMENTS
2006; 77 (10)
View details for DOI 10.1063/1.2235648
View details for Web of Science ID 000241722800215
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3 omega transmitted beam diagnostic at the Omega Laser Facility
REVIEW OF SCIENTIFIC INSTRUMENTS
2006; 77 (10)
View details for DOI 10.1063/1.2221911
View details for Web of Science ID 000241722800081
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Thomson-scattering techniques to diagnose local electron and ion temperatures, density, and plasma wave amplitudes in laser produced plasmas (invited)
REVIEW OF SCIENTIFIC INSTRUMENTS
2006; 77 (10)
View details for DOI 10.1063/1.2336451
View details for Web of Science ID 000241722800096
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Thomson scattering from a shock front
REVIEW OF SCIENTIFIC INSTRUMENTS
2006; 77 (10)
View details for DOI 10.1063/1.2220069
View details for Web of Science ID 000241722800078
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Laser light backscatter from intermediate and high Z plasmas
PHYSICS OF PLASMAS
2006; 13 (9)
View details for DOI 10.1063/1.2231510
View details for Web of Science ID 000240877800041
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Generalized x-ray scattering cross section from nonequilibrium plasmas
PHYSICAL REVIEW E
2006; 74 (2)
Abstract
We propose a modified x-ray form factor that describes the scattering cross section in warm dense matter valid for both the plasma and the solid (crystalline) state. Our model accounts for the effect of lattice correlations on the electron-electron dynamic structure, as well as provides a smooth transition between the solid and the plasma scattering cross sections. In addition, we generalize the expression of the dynamic structure in the case of a two-temperature system (with different electron and ion temperatures). This work provides a unified description of the x-ray scattering processes in warm and dense matter, as the one encountered in inertial confinement fusion, laboratory astrophysics, material science, and high-energy density physics and it can be used to verify temperature relaxation mechanisms in such environments.
View details for DOI 10.1103/PhysRevE.74.026402
View details for Web of Science ID 000240238200052
View details for PubMedID 17025545
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Efficient coupling of 527 nm laser beam power to a long scalelength plasma
JOURNAL DE PHYSIQUE IV
2006; 133: 321-324
View details for DOI 10.1051/jp4:2006133064
View details for Web of Science ID 000239228900064
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Measurements of gas filled halfraum energetics at the national ignition facility using a single quad
JOURNAL DE PHYSIQUE IV
2006; 133: 919-923
View details for DOI 10.1051/jp4:2006133185
View details for Web of Science ID 000239228900185
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Laser coupling to reduced-scale targets at NIF early light
JOURNAL DE PHYSIQUE IV
2006; 133: 237-241
View details for DOI 10.1051/jp4:2006133048
View details for Web of Science ID 000239228900048
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X-ray flux and X-ray burnthrough experiments on reduced-scale targets at the NIF and OMEGA lasers
JOURNAL DE PHYSIQUE IV
2006; 133: 1205-1208
View details for DOI 10.1051/jp4:2006133247
View details for Web of Science ID 000239228900247
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The first experiments on the national ignition facility
JOURNAL DE PHYSIQUE IV
2006; 133: 43-45
View details for DOI 10.1051/jp4:2006133009
View details for Web of Science ID 000239228900009
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Limits on collective X-ray scattering imposed by coherence
EUROPHYSICS LETTERS
2006; 74 (4): 637-643
View details for DOI 10.1209/epl/i2005-10570-7
View details for Web of Science ID 000237471700011
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Measurement of carbon ionization balance in high-temperature plasma mixtures by temporally resolved X-ray scattering
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
2006; 99 (1-3): 225-237
View details for DOI 10.1016/j.jqsrt.2005.05.017
View details for Web of Science ID 000235111300019
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X-ray probe development for collective scattering measurements in dense plasmas
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
2006; 99 (1-3): 636-648
View details for DOI 10.1016/j.jqsrt.2005.05.051
View details for Web of Science ID 000235111300054
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Electron-density scaling of conversion efficiency of laser energy into L-shell X-rays
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
2006; 99 (1-3): 186-198
View details for DOI 10.1016/j.jqsrt.2005.04.008
View details for Web of Science ID 000235111300016
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First hohlraum drive studies on the National Ignition Facility
PHYSICS OF PLASMAS
2006; 13 (5)
View details for DOI 10.1063/1.2178783
View details for Web of Science ID 000237943000132
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Thomson-scattering measurements of high electron temperature hohlraum plasmas for laser-plasma interaction studies
PHYSICS OF PLASMAS
2006; 13 (5)
View details for DOI 10.1063/1.2203232
View details for Web of Science ID 000237943000050
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Gas-filled hohlraum experiments at the National Ignition Facility
PHYSICS OF PLASMAS
2006; 13 (5)
View details for DOI 10.1063/1.2183907
View details for Web of Science ID 000237943000136
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Hot surface ionic line emission and cold K-inner shell emission from petawatt-laser-irradiated Cu foil targets
PHYSICS OF PLASMAS
2006; 13 (4)
View details for DOI 10.1063/1.2188912
View details for Web of Science ID 000237137000037
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High energy density science with FELs, intense short pulse tunable x-ray sources
HIGH-POWER LASER ABLATION VI, PTS 1 AND 2
2006; 6261
View details for DOI 10.1117/12.674424
View details for Web of Science ID 000239450500001
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Integrated laser-target interaction experiments on the RAL petawatt laser
PLASMA PHYSICS AND CONTROLLED FUSION
2005; 47: B833-B840
View details for DOI 10.1088/0741-3335/47/12B/S65
View details for Web of Science ID 000234420700067
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First laser-plasma interaction and hohlraum experiments on the National Ignition Facility
PLASMA PHYSICS AND CONTROLLED FUSION
2005; 47: B405-B417
View details for DOI 10.1088/0741-3335/47/12B/S29
View details for Web of Science ID 000234420700031
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Radiation-driven hydrodynamics of high-Z hohlraums on the National Ignition Facility
PHYSICAL REVIEW LETTERS
2005; 95 (21)
Abstract
The first hohlraum experiments on the National Ignition Facility (NIF) using the initial four laser beams tested radiation temperature limits imposed by plasma filling. For a variety of hohlraum sizes and pulse lengths, the measured x-ray flux shows signatures of filling that coincide with hard x-ray emission from plasma streaming out of the hohlraum. These observations agree with hydrodynamic simulations and with an analytical model that includes hydrodynamic and coronal radiative losses. The modeling predicts radiation temperature limits with full NIF (1.8 MJ), greater, and of longer duration than required for ignition hohlraums.
View details for DOI 10.1103/PhysRevLett.95.215004
View details for Web of Science ID 000233362100032
View details for PubMedID 16384150
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Measurement of the dispersion of thermal ion-acoustic fluctuations in high-temperature laser plasmas using multiple-wavelength Thomson scattering
PHYSICAL REVIEW LETTERS
2005; 95 (19)
Abstract
The dispersion of ion-acoustic fluctuations has been measured using a novel technique that employs multiple color Thomson-scattering diagnostics to measure the frequency spectrum for two separate thermal ion-acoustic fluctuations with significantly different wave vectors. The plasma fluctuations are shown to become dispersive with increasing electron temperature. We demonstrate that this technique allows a time resolved local measurement of electron density and temperature in inertial confinement fusion plasmas.
View details for DOI 10.1103/PhysRevLett.95.195005
View details for Web of Science ID 000233062900032
View details for PubMedID 16383991
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Supersonic propagation of ionization waves in an underdense, laser-produced plasma
PHYSICS OF PLASMAS
2005; 12 (6)
View details for DOI 10.1063/1.1927540
View details for Web of Science ID 000229700400059
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Laser coupling to reduced-scale hohlraum targets at the early light program of the National Ignition Facility
PHYSICS OF PLASMAS
2005; 12 (5)
View details for DOI 10.1063/1.188012
View details for Web of Science ID 000229276200134
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Intensity limits for propagation of 0.527 mu m laser beams through large-scale-length plasmas for inertial confinement fusion
PHYSICAL REVIEW LETTERS
2005; 94 (8)
Abstract
We have established the intensity limits for propagation of a frequency-doubled (2omega, 527 nm) high intensity interaction beam through an underdense large-scale-length plasma. We observe good beam transmission at laser intensities at or below 2x10(14) W/cm(2) and a strong reduction at intensities up to 10(15) W/cm(2) due to the onset of parametric scattering instabilities. We show that temporal beam smoothing by spectral dispersion allows a factor of 2 higher intensities while keeping the beam spray constant, which establishes frequency-doubled light as an option for ignition and burn in inertial confinement fusion experiments.
View details for DOI 10.1103/PhysRevLett.94.085005
View details for Web of Science ID 000227386000036
View details for PubMedID 15783902
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Experimental characterization of a strongly coupled solid density plasma generated in a short-pulse laser target interaction
CONTRIBUTIONS TO PLASMA PHYSICS
2005; 45 (3-4): 284-292
View details for DOI 10.1002/ctpp.200510032
View details for Web of Science ID 000230380000018
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Progress in long scale length laser-plasma interactions
NUCLEAR FUSION
2004; 44 (12): S185-S190
View details for DOI 10.1088/0029-5515/44/12/S08
View details for Web of Science ID 000226176900009
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A summary of explorations into the use of green light for high-gain, high-yield experiments on the National Ignition Facility
NUCLEAR FUSION
2004; 44 (12): S140-S148
View details for DOI 10.1088/0029-5515/44/12/S04
View details for Web of Science ID 000226176900005
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Dante soft x-ray power diagnostic for National Ignition Facility
REVIEW OF SCIENTIFIC INSTRUMENTS
2004; 75 (10): 3759-3761
View details for DOI 10.1063/1.1788872
View details for Web of Science ID 000224755900114
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Full aperture backscatter station measurement system on the National Ignition Facility
REVIEW OF SCIENTIFIC INSTRUMENTS
2004; 75 (10): 4177-4179
View details for DOI 10.1063/1.1791749
View details for Web of Science ID 000224755900239
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Implementation of a near backscattering imaging system on the National Ignition Facility
REVIEW OF SCIENTIFIC INSTRUMENTS
2004; 75 (10): 4183-4186
View details for DOI 10.1063/1.1789594
View details for Web of Science ID 000224755900241
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Full-aperture backscatter measurements on the National Ignition Facility
REVIEW OF SCIENTIFIC INSTRUMENTS
2004; 75 (10): 4168-4170
View details for DOI 10.1063/1.1789592
View details for Web of Science ID 000224755900236
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Calibration of initial measurements from the full aperture backscatter system on the National Ignition Facility
REVIEW OF SCIENTIFIC INSTRUMENTS
2004; 75 (10): 4174-4176
View details for DOI 10.1063/1.1789593
View details for Web of Science ID 000224755900238
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Omega dante soft x-ray power diagnostic component calibration at the National Synchrotron Light Source
REVIEW OF SCIENTIFIC INSTRUMENTS
2004; 75 (10): 3768-3771
View details for DOI 10.1063/1.1789603
View details for Web of Science ID 000224755900117
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Transmitted laser beam diagnostic at the Omega laser facility
REVIEW OF SCIENTIFIC INSTRUMENTS
2004; 75 (10): 4171-4173
View details for DOI 10.1063/1.1787602
View details for Web of Science ID 000224755900237
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Implementation of a high energy 4 omega probe beam on the Omega laser
REVIEW OF SCIENTIFIC INSTRUMENTS
2004; 75 (10): 3906-3908
View details for DOI 10.1063/1.1789247
View details for Web of Science ID 000224755900158
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X-ray line measurements with high efficiency Bragg crystals
REVIEW OF SCIENTIFIC INSTRUMENTS
2004; 75 (10): 3747-3749
View details for DOI 10.1063/1.1788870
View details for Web of Science ID 000224755900110
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Measurement of the absolute hohlraum-wall albedo under ignition foot drive conditions
PHYSICAL REVIEW LETTERS
2004; 93 (6)
Abstract
We present measurements of the absolute albedos of hohlraums made from gold or from high-Z mixtures. The measurements are performed over the range of radiation temperatures (70-100 eV) expected during the foot of an indirect-drive temporally shaped ignition laser pulse, where accurate knowledge of the wall albedo (i.e., soft x-ray wall reemission) is most critical for determining capsule radiation symmetry. We find that the gold albedo agrees well with calculations using the supertransition array opacity model, potentially providing additional margin for inertial confinement fusion ignition.
View details for DOI 10.1103/PhysRevLett.93.065002
View details for Web of Science ID 000223138200026
View details for PubMedID 15323638
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Observation of the parametric two-ion decay instability with Thomson scattering
PHYSICAL REVIEW LETTERS
2004; 93 (4)
Abstract
We present the first direct experimental observation of the parametric two-ion decay instability of ion-acoustic waves driven by a high intensity (5 x 10(15) W cm(-2)) laser beam in a laser produced high-Z plasma. Using two separate Thomson scattering diagnostics simultaneously, we directly measure the scattering from thermal ion-acoustic fluctuations, the primary ion waves that are driven to large amplitudes by the high intensity beam, and the two-ion decay products. The decay products are shown to be present only where the interaction takes place and their k spectrum is broad.
View details for DOI 10.1103/PhysRevLett.93.045004
View details for Web of Science ID 000222856400034
View details for PubMedID 15323769
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Direct observation of the saturation of stimulated Brillouin scattering by ion-trapping-induced frequency shifts
PHYSICAL REVIEW LETTERS
2004; 93 (3)
Abstract
We report the first measurement of the saturation of stimulated Brillouin scattering (SBS) by an ion-trapping-induced frequency shift, which was achieved by directly measuring the amplitude and absolute frequency of SBS-driven ion-acoustic waves (IAW). A frequency shift of up to 30% and a simultaneous saturation of driven IAW and SBS reflectivity were observed. The scaling of the frequency shift with the IAW amplitude compares well with theoretical calculations. We have further measured fast 30 ps oscillations of the SBS-driven IAW amplitude induced by the frequency shift.
View details for DOI 10.1103/PhysRevLett.93.035001
View details for Web of Science ID 000222691900022
View details for PubMedID 15323827
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Effect of nonlocal transport on heat-wave propagation
PHYSICAL REVIEW LETTERS
2004; 92 (20)
Abstract
We present the first direct measurements of spatially and temporally resolved temperature and density profiles produced by nonlocal transport in a laser plasma. Absolutely calibrated measurements have been performed by Rayleigh scattering and by resolving the ion-acoustic wave spectra across the plasma volume with Thomson scattering. We find that the electron temperature and density profiles disagree with flux-limited models, but are consistent with nonlocal transport modeling.
View details for DOI 10.1103/PhysRevLett.92.205006
View details for Web of Science ID 000221541300035
View details for PubMedID 15169364
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Electronic structure measurements of dense plasmas
PHYSICS OF PLASMAS
2004; 11 (5): 2754-2762
View details for DOI 10.1063/1.1689664
View details for Web of Science ID 000221122600121
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Prospects for high-gain, high yield National Ignition Facility targets driven by 2 omega (green) light
PHYSICS OF PLASMAS
2004; 11 (5): 2738-2745
View details for DOI 10.1063/1.1687725
View details for Web of Science ID 000221122600119
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First measurement of backscatter dependence on ion acoustic damping in a high density helium/hydrogen laser-plasma
PHYSICS OF PLASMAS
2004; 11 (5): 2060-2067
View details for DOI 10.1063/1.1701894
View details for Web of Science ID 000221122600042
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Effects of plasma composition on backscatter, hot electron production, and propagation in underdense plasmas
PHYSICS OF PLASMAS
2004; 11 (5): 2709-2715
View details for DOI 10.1063/1.1651490
View details for Web of Science ID 000221122600115
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Thomson scattering measurements of heat flow in a laser-produced plasma
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
2004; 37 (7): 1541-1551
View details for DOI 10.1088/0953-4075/37/7/013
View details for Web of Science ID 000221071700040
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The physics basis for ignition using indirect-drive targets on the National Ignition Facility
PHYSICS OF PLASMAS
2004; 11 (2): 339-491
View details for DOI 10.1063/1.1578638
View details for Web of Science ID 000188282100001
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Effects of ion trapping on crossed-laser-beam stimulated Brillouin scattering
PHYSICS OF PLASMAS
2004; 11 (1): 231-244
View details for DOI 10.1063/1.1630573
View details for Web of Science ID 000187430100026
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Observation of ion wave decay products of Langmuir waves generated by stimulated Raman scattering in ignition scale plasmas
PHYSICS OF PLASMAS
2003; 10 (8): 3422-3425
View details for DOI 10.1063/1.1590317
View details for Web of Science ID 000184491800045
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Scaling of saturated stimulated Raman scattering with temperature and intensity in ignition scale plasmas
PHYSICS OF PLASMAS
2003; 10 (7): 2948-2955
View details for DOI 10.1063/1.1580814
View details for Web of Science ID 000183585500037
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Investigation of the onset and development of forward scattering in an underdense plasma
PHYSICAL REVIEW LETTERS
2003; 90 (24)
Abstract
We investigate the distortion of a spatial intensity modulation imposed on a 527 nm f/10 probe beam as it transmits through an underdense plasma characterized with Thomson scattering. Combining the measurements with full wave simulations of beam propagation through the entire plasma show that the key features of the data can be reproduced using the Kaiser thermal transport model.
View details for DOI 10.1103/PhysRevLett.90.245001
View details for Web of Science ID 000183642800015
View details for PubMedID 12857194
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Strong coupling corrections in the analysis of x-ray Thomson scattering measurements
JOURNAL OF PHYSICS A-MATHEMATICAL AND GENERAL
2003; 36 (22): 5971-5980
View details for Web of Science ID 000183614400022
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X-ray scattering from solid density plasmas
PHYSICS OF PLASMAS
2003; 10 (6): 2433-2441
View details for DOI 10.1063/1.1570420
View details for Web of Science ID 000183316500027
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Demonstration of spectrally resolved x-ray scattering in dense plasmas
PHYSICAL REVIEW LETTERS
2003; 90 (17)
Abstract
We present the first spectrally resolved x-ray scattering measurements from solid-density plasmas. The scattering spectra show the broadened Compton down-shifted feature allowing us to determine the electron temperature and density with high accuracy. In the low temperature limit, our data indicate that the ionization balance reflects the electrons in the conduction band consistent with calculations that include quantum mechanical corrections to the interaction potential.
View details for DOI 10.1103/PhysRevLett.90.175002
View details for Web of Science ID 000182603800023
View details for PubMedID 12786077
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Modeling the nonlinear saturation of stimulated Brillouin backscatter in laser heated plasmas
PHYSICS OF PLASMAS
2003; 10 (5): 1822-1828
View details for DOI 10.1063/1.1557055
View details for Web of Science ID 000182450200040
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Stimulated Brillouin scattering in the saturated regime
PHYSICS OF PLASMAS
2003; 10 (5): 1846-1853
View details for DOI 10.1063/1.1542887
View details for Web of Science ID 000182450200042
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Direct observation of stimulated-Brillouin-scattering detuning by a velocity gradient
PHYSICAL REVIEW LETTERS
2003; 90 (15)
Abstract
We report the first direct evidence of detuning of stimulated Brillouin scattering (SBS) by a velocity gradient, which was achieved by directly measuring the frequency shift of the SBS-driven acoustic wave relative to the local resonant acoustic frequency. We show that in the expanding part of the plasma, ion-acoustic waves are driven off resonance which leads to the saturation of the SBS instability. These measurements are well reproduced by fluid simulations that include the measured flow.
View details for DOI 10.1103/PhysRevLett.90.155003
View details for Web of Science ID 000182320200022
View details for PubMedID 12732042
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Time and spatially resolved measurements of x-ray burnthrough and re-emission in Au and Au : Dy : Nd foils
REVIEW OF SCIENTIFIC INSTRUMENTS
2003; 74 (3): 2186-2190
View details for DOI 10.1063/1.1537866
View details for Web of Science ID 000181530500184
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Theoretical model of x-ray scattering as a dense matter probe
PHYSICAL REVIEW E
2003; 67 (2)
Abstract
We present analytical expressions for the dynamic structure factor, or form factor S(k,omega), which is the quantity describing the x-ray cross section from a dense plasma or a simple liquid. Our results, based on the random phase approximation for the treatment on the charged particle coupling, can be applied to describe scattering from either weakly coupled classical plasmas or degenerate electron liquids. Our form factor correctly reproduces the Compton energy down-shift and the known Fermi-Dirac electron velocity distribution for S(k,omega) in the case of a cold degenerate plasma. The usual concept of scattering parameter is also reinterpreted for the degenerate case in order to include the effect of the Thomas-Fermi screening. The results shown in this work can be applied to interpreting x-ray scattering in warm dense plasmas occurring in inertial confinement fusion experiments or for the modeling of solid density matter found in the interior of planets.
View details for DOI 10.1103/PhysRevE.67.026412
View details for Web of Science ID 000181520300098
View details for PubMedID 12636827
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Observation of saturation of energy transfer between copropagating beams in a flowing plasma
PHYSICAL REVIEW LETTERS
2002; 89 (21)
Abstract
Experiments demonstrate energy and power transfer between copropagating, same frequency, beams crossing at a small angle in a plasma with a Mach 1 flow. The process is interpreted as amplification of the low intensity probe beam by the stimulated scatter of the high intensity pump beam. The observed probe amplification increases slowly with pump intensity and decreases with probe intensity, indicative of saturation limiting the energy and power transfer due to ion-wave nonlinearities and localized pump depletion. The results are consistent with numerical modeling including ion-wave nonlinearities.
View details for DOI 10.1103/PhysRevLett.89.215003
View details for Web of Science ID 000179068000028
View details for PubMedID 12443421
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Observation of ion heating by stimulated-Brillouin-scattering-driven ion-acoustic waves using Thomson scattering
PHYSICS OF PLASMAS
2002; 9 (11): 4709-4718
View details for DOI 10.1063/1.1508776
View details for Web of Science ID 000178789900035
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K-shell spectroscopy of an independently diagnosed uniaxially expanding laser-produced aluminum plasma
PHYSICAL REVIEW E
2002; 66 (2)
Abstract
We present detailed spectroscopic analysis of the primary K-shell emission lines from a uniaxially expanding laser-produced hydrogenic and heliumlike aluminum plasma. The spectroscopic measurements are found to be consistent with time-dependent hydrodynamic properties of the plasma, measured using Thomson scattering and shadowgraphy. The K-shell population kinetics code FLY with the measured hydrodynamic parameters is used to generate spectra that are compared to the experimental spectra. Excellent agreement is found between the measured and calculated spectra for a variety of experimental target widths employed to produce plasmas with different optical depths. The peak emission from the hydrogenic Lyman series is determined to be from a temporal and spatial region where the hydrodynamic parameters are essentially constant. This allows a single steady-state solution of FLY to be used to deduce the electron temperature and density, from the measured line ratios and linewidths, for comparison with the Thomson and shadowgraphy data. These measurements are found to agree well with time-dependent calculations, and provide further validation for the FLY calculations of the ionization and excitation balance for a K-shell aluminum plasma. We also discuss the possible application of this data as a benchmark for hydrodynamic simulations and ionization/excitation balance calculations.
View details for DOI 10.1103/PhysRevE.66.026410
View details for Web of Science ID 000177971300079
View details for PubMedID 12241300
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Anomalous absorption of high-energy green laser light in high-Z plasmas
PHYSICAL REVIEW LETTERS
2002; 88 (23)
Abstract
We observe strong anomalous absorption of green laser light in mm-scale high-temperature gold plasmas. Both the laser light absorption and the resulting increase of the electron temperature, which was measured independently with Thomson scattering, have been successfully modeled by including enhanced collisions due to heat-flux driven ion acoustic fluctuations. Calculations that include only inverse bremsstrahlung significantly underestimate the experimental laser absorption and the electron temperature.
View details for DOI 10.1103/PhysRevLett.88.235002
View details for Web of Science ID 000175860500032
View details for PubMedID 12059370
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Measurements of nonlinear growth of ion-acoustic waves in two-ion-species plasmas with Thomson scattering
PHYSICAL REVIEW LETTERS
2002; 88 (10)
Abstract
We report the first Thomson-scattering measurements of the growth of ion-acoustic waves in well-characterized multi-ion-species plasmas consisting of gold and beryllium. We observe that only the berylliumlike mode grows, verifying linear kinetic theory. In addition, a twofold increase in ion temperature is measured when ion-acoustic waves are excited to large amplitudes by stimulated Brillouin scattering (SBS). This increase in ion temperature is a strong indication of hot ions due to trapping. We explain the measured SBS reflectivity by nonlinear detuning of the SBS instability due to these trapping effects.
View details for DOI 10.1103/PhysRevLett.88.105003
View details for Web of Science ID 000174342000035
View details for PubMedID 11909364
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Thomson scattering in inertial confinement fusion research
ADVANCED DIAGNOSTICS FOR MAGNETIC AND INERTIAL FUSION
2002: 303-310
View details for Web of Science ID 000177840700055
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Calculations and measurements of x-ray Thomson scattering spectra in warm dense matter
SPECTRAL LINE SHAPES
2002; 645: 359-368
View details for Web of Science ID 000180453100046
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Observation of saturated brillouin instability in fusion plasmas with Thomson scattering
Frontier Science Research Conference on Laser - Matter Interaction
STEFAN UNIV PRESS. 2002: 133–137
View details for Web of Science ID 000181496100007
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A Thomson scattering post-processor for the MEDUSA hydrocode
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
2001; 71 (2-6): 383-395
View details for Web of Science ID 000171262300025
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Dense matter characterization by X-ray Thomson scattering
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
2001; 71 (2-6): 465-478
View details for Web of Science ID 000171262300031
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Ionization balance in inertial confinement fusion hohlraum plasmas
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
2001; 71 (2-6): 355-363
View details for Web of Science ID 000171262300022
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Detailed hydrodynamic and X-ray spectroscopic analysis of a laser-produced rapidly-expanding aluminium plasma
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
2001; 71 (2-6): 237-247
View details for Web of Science ID 000171262300012
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Ionization balance in inertial confinement fusion hohlraums
PHYSICAL REVIEW LETTERS
2001; 87 (4)
Abstract
We present the first x-ray spectroscopic measurements of the ionization balance in inertial confinement fusion hohlraums supported by 4omega Thomson scattering diagnostics. The experimental data show agreement with non-LTE radiation-hydrodynamic calculations of the averaged Au charge state and electron temperatures. These findings are consistent with the successful integrated modeling of the hohlraum radiation fields. Comparisons with detailed synthetic spectra calculations show that the experimental ionization distribution is slightly shifted indicating nonsteady state kinetics.
View details for DOI 10.1103/PhysRevLett.87.045002
View details for Web of Science ID 000170060700022
View details for PubMedID 11461624
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Reduction of stimulated scattering losses from hohlraum plasmas with laser beam smoothing
PHYSICS OF PLASMAS
2001; 8 (5): 1692-1696
View details for Web of Science ID 000168187800032
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Backscatter reduction using combined spatial, temporal, and polarization beam smoothing in a long-scale-length laser plasma
PHYSICAL REVIEW LETTERS
2001; 86 (13): 2810-2813
Abstract
Spatial, temporal, and polarization smoothing schemes are combined for the first time to reduce to a few percent the total stimulated backscatter of a NIF-like probe laser beam (2x10(15) W/cm (2), 351 nm, f/8) in a long-scale-length laser plasma. Combining temporal and polarization smoothing reduces simulated Brillouin scattering and simulated Raman scattering (SRS) up to an order of magnitude although neither smoothing scheme by itself is uniformly effective. The results agree with trends observed in simulations performed with the laser-plasma interaction code F3D simulations [R. L. Berger et al., Phys. Plasma 6, 1043 (1999)].
View details for Web of Science ID 000167693000028
View details for PubMedID 11290045
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Thomson scattering measurements of saturated ion waves in laser fusion plasmas
PHYSICAL REVIEW LETTERS
2001; 86 (12): 2565-2568
Abstract
We have measured the characteristics of saturated ion-acoustic waves in inertial confinement fusion plasmas. A 263-nm probe laser has been applied to simultaneous Thomson scatter on both ion-acoustic waves excited by thermal electrostatic fluctuations and by stimulated Brillouin scattering of a kilojoule laser beam of varying intensity. The Thomson scattering spectra show saturated ion-wave amplitudes for intensities above 5x10(14) W cm(-2) consistent with three dimensional nonlinear wave modeling.
View details for Web of Science ID 000167573800019
View details for PubMedID 11289981
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Electron distribution function in laser heated plasmas
PHYSICS OF PLASMAS
2001; 8 (2): 550-556
View details for Web of Science ID 000166820800020
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Warm, dense plasma characterization by x-ray Thomson scattering
ECLIM 2000: 26TH EUROPEAN CONFERENCE ON LASER INTERACTION WITH MATTER
2001; 4424: 112-119
View details for Web of Science ID 000169324100018
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Modeling the backscatter and transmitted light of high power smoothed beams with pF3D, a massively parallel laser plasma interaction code
ECLIM 2000: 26TH EUROPEAN CONFERENCE ON LASER INTERACTION WITH MATTER
2001; 4424: 206-211
View details for Web of Science ID 000169324100038
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Status of our understanding and modeling of x-ray coupling efficiency in laser heated hohlraums
PHYSICS OF PLASMAS
2001; 8 (1): 260-265
View details for Web of Science ID 000166400600036
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Experimental study of laser beam transmission and power accounting in a large scale length laser plasma
PHYSICS OF PLASMAS
2000; 7 (8): 3388-3398
View details for Web of Science ID 000088239900030
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Accuracy of K-shell spectra modeling in high-density plasmas
PHYSICAL REVIEW E
2000; 62 (2): 2728-2738
Abstract
We present spectroscopic measurements of the helium-like and lithium-like argon emission supported by Thomson scattering diagnostics on gas bag targets. These data provide critical tests of plasma spectroscopic K-shell models. In particular, we have measured the line radiation in the wavelength region of the He-like Ar 1s(2)-1s3l transition (He-beta) that is of interest for density and temperature measurements of plasmas from gas-filled targets (n(e)=10(21) cm(-3)), laser ablation targets (n(e)=10(22) cm(-3)), and inertial confinement fusion capsule implosions (n(e)>/=10(24) cm(-3)). The spectra show lithium-like dielectronic satellites on the red wing of the He-beta line that are temperature sensitive and are known to influence the shape of the Stark-broadened line profiles observed from implosions. To examine the kinetics modeling of this complex, i.e., the He-beta and its associated satellites, we have performed experiments in gas bag plasmas at densities of (0.6-1.1)x10(21) cm(-3) where we independently determine the electron temperature with ultraviolet Thomson scattering. The comparison of the satellite intensities with kinetics modeling shows good agreement for satellites whose upper states are populated by dielectronic capture, but shows discrepancies for inner-shell collisional excited transitions.
View details for Web of Science ID 000088960800039
View details for PubMedID 11088753
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Ionization processes and charge-state distribution in a highly ionized high-Z laser-produced plasma
PHYSICAL REVIEW LETTERS
2000; 85 (5): 992-995
Abstract
The charge-state distribution in a well-characterized highly ionized Au plasma was accurately determined using time-resolved x-ray spectroscopy. Simultaneous measurements of the electron temperature and density allow the first direct comparisons with nonlocal thermodynamic equilibrium model predictions for the charge-state distribution of a highly ionized high- Z plasma in a nonradiative environment. The importance of two-electron atomic processes is clearly demonstrated.
View details for Web of Science ID 000088457000023
View details for PubMedID 10991457
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Hohlraum energetics with smoothed laser beams
PHYSICS OF PLASMAS
2000; 7 (6): 2585-2593
View details for Web of Science ID 000087455500043
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Experimental investigation of short scalelength density fluctuations in laser-produced plasmas
PHYSICS OF PLASMAS
2000; 7 (5): 2114-2125
View details for Web of Science ID 000086511000064
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Analysis of discrepancies between quantal and semiclassical calculations of electron impact broadening in plasmas
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
2000; 65 (1-3): 15-22
View details for Web of Science ID 000084836700003
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Modeling of Thomson scattering spectra in high-Z, laser-produced plasmas
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
2000; 127 (2): 459-463
View details for Web of Science ID 000088346900040
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Testing astrophysical radiation hydrodynamics codes with hypervelocity jet experiments on the nova laser
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
2000; 127 (2): 497-502
View details for Web of Science ID 000088346900046
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Detailed characterization of laser plasmas for benchmarking of radiation-hydrodynamic modeling
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
2000; 65 (1-3): 253-271
View details for Web of Science ID 000084836700024
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Accurate determination of the charge state distribution in a well characterized highly ionized Au plasma
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
2000; 65 (1-3): 231-241
View details for Web of Science ID 000084836700022
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Towards an experimental benchmark for aluminum X-ray spectra
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
2000; 65 (1-3): 23-30
View details for Web of Science ID 000084836700004
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On the accuracy of x-ray spectra modeling of inertial confinement fusion plasmas
12th Topical Conference on Atomic Processes in Plasmas
AMER INST PHYSICS. 2000: 3–14
View details for Web of Science ID 000166658200001
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Using high resolution X-ray spectroscopy of laser and EBIT plasma sources to test atomic models
12th Topical Conference on Atomic Processes in Plasmas
AMER INST PHYSICS. 2000: 203–216
View details for Web of Science ID 000166658200017
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Thomson scattering in inertial confinement fusion research
CONTRIBUTIONS TO PLASMA PHYSICS
2000; 40 (1-2): 36-45
View details for Web of Science ID 000086082300004
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Observation of the nonlinear saturation of Langmuir waves driven by ponderomotive force in a large scale plasma
PHYSICAL REVIEW LETTERS
1999; 83 (15): 2965-2968
View details for Web of Science ID 000083041400025
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Radiative jet experiments of astrophysical interest using intense lasers
PHYSICAL REVIEW LETTERS
1999; 83 (10): 1982-1985
View details for Web of Science ID 000082392800021
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First measurement of short length-scale density fluctuations in a large laser plasma
PHYSICAL REVIEW LETTERS
1999; 83 (9): 1783-1786
View details for Web of Science ID 000082242600021
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Observation of resonant energy transfer between identical-frequency laser beams
PHYSICS OF PLASMAS
1999; 6 (5): 2144-2149
View details for Web of Science ID 000079969500057
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Thomson scattering from laser plasmas
PHYSICS OF PLASMAS
1999; 6 (5): 2117-2128
View details for Web of Science ID 000079969500054
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Thomson scattering from high-Z laser-produced plasmas
PHYSICAL REVIEW LETTERS
1999; 82 (1): 97-100
View details for Web of Science ID 000077887000024
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A spectroscopic coupling study for some carbon-like species
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
1999; 61 (2): 215-218
View details for Web of Science ID 000077210800007
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X-ray spectroscopy from fusion plasmas
SPECTRAL LINE SHAPES, VOL 10
1999; 467: 49-63
View details for Web of Science ID 000080238100005
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High-energy 4 omega probe laser for laser-plasma experiments at Nova
REVIEW OF SCIENTIFIC INSTRUMENTS
1999; 70 (1): 1089-1092
View details for Web of Science ID 000078278900223
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Measurements of near forward scattered laser light in a large inertial confinement fusion plasma (invited)
REVIEW OF SCIENTIFIC INSTRUMENTS
1999; 70 (1): 677-681
View details for Web of Science ID 000078278900109
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Observation of energy transfer between identical-frequency laser beams in a flowing plasma
PHYSICAL REVIEW LETTERS
1998; 81 (11): 2248-2251
View details for Web of Science ID 000075897300017
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Measurements of suprathermal electrons in Hohlraum plasmas with x-ray spectroscopy
PHYSICAL REVIEW LETTERS
1998; 81 (2): 365-368
View details for Web of Science ID 000074750400031
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Improved gas-filled hohlraum performance on Nova with beam smoothing
PHYSICS OF PLASMAS
1998; 5 (5): 1927-1934
View details for Web of Science ID 000073623700044
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Stark broadening along the berylliumlike sequence
PHYSICAL REVIEW E
1998; 57 (5): 5972-5977
View details for Web of Science ID 000073768000062
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Evidence of plasma fluctuations and their effect on the growth of stimulated Brillouin and stimulated Raman scattering in laser plasmas
PHYSICS OF PLASMAS
1998; 5 (5): 1973-1980
View details for Web of Science ID 000073623700050
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Energetics of inertial confinement fusion Hohlraum plasmas
PHYSICAL REVIEW LETTERS
1998; 80 (13): 2845-2848
View details for Web of Science ID 000072757000023
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Thomson scattering from inertial-confinement-fusion Hohlraum plasmas
PHYSICAL REVIEW LETTERS
1997; 79 (7): 1277-1280
View details for Web of Science ID A1997XR28700026
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Observation of multiple mechanisms for stimulating ion waves in ignition scale plasmas
PHYSICS OF PLASMAS
1997; 4 (5): 1800-1810
View details for Web of Science ID A1997WY64700036
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X-ray diagnostics of hohlraum plasma flow
REVIEW OF SCIENTIFIC INSTRUMENTS
1997; 68 (1): 831-833
View details for Web of Science ID A1997WD23700143
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Laser scattering in large scale length plasmas relevant to National Ignition Facility hohlraums
16th International Conference on Fusion Energy
INT ATOMIC ENERGY AGENCY. 1997: 181–186
View details for Web of Science ID 000079102600019
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Thomson scattering from inertial confinement fusion plasmas
13th International Conference on Laser Interaction and Related Plasma Phenomena (LIRPP 97)
AIP PRESS. 1997: 95–113
View details for Web of Science ID 000071320600011
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Experiments on hot and dense laser-produced plasmas
13th International Conference on Spectral Line Shapes (13th ICSLS)
AMER INST PHYSICS. 1997: 35–44
View details for Web of Science ID A1997BH28Z00011
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Thomson scattering from two-species laser-produced plasmas (invited)
REVIEW OF SCIENTIFIC INSTRUMENTS
1997; 68 (1): 641-646
View details for Web of Science ID A1997WD23700095
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Electron temperature and density measurements in laser-produced large-scale-length gas-bag plasmas by x-ray spectroscopy
PHYSICAL REVIEW E
1997; 55 (1): 927-938
View details for Web of Science ID A1997WD54600041
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Investigation of a short-wavelength laser plasma of a gas-liner pinch discharge
PHYSICAL REVIEW E
1997; 55 (1): 939-946
View details for Web of Science ID A1997WD54600042
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Imaging backscattered and near to backscattered light in ignition scale plasmas (invited)
REVIEW OF SCIENTIFIC INSTRUMENTS
1997; 68 (1): 636-640
View details for Web of Science ID A1997WD23700094
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Thomson scattering in the corona of laser-produced gold plasmas
REVIEW OF SCIENTIFIC INSTRUMENTS
1997; 68 (1): 668-671
View details for Web of Science ID A1997WD23700101
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Line profile measurements in a gas-liner pinch discharge
13th International Conference on Spectral Line Shapes (13th ICSLS)
AMER INST PHYSICS. 1997: 71–76
View details for Web of Science ID A1997BH28Z00021
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Investigation of the He II P-alpha and He II P-beta transitions at high densities
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
1996; 29 (18): 4107-4125
View details for Web of Science ID A1996VK01600008
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Effect of ion-wave damping on stimulated Raman scattering in high-Z laser-produced plasmas
PHYSICAL REVIEW LETTERS
1996; 77 (13): 2706-2709
View details for Web of Science ID A1996VH76700028
View details for PubMedID 10062025
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Observation of two ion-acoustic waves in a two-species laser-produced plasma with Thomson scattering
PHYSICAL REVIEW LETTERS
1996; 77 (8): 1496-1499
View details for Web of Science ID A1996VC33600022
View details for PubMedID 10063093
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Investigation of electron-proton drifts with Thomson scattering
JOURNAL OF ATMOSPHERIC AND TERRESTRIAL PHYSICS
1996; 58 (8-9): 1077-?
View details for Web of Science ID A1996UH87000018
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Laser-plasma interactions in ignition-scale hohlraum plasmas
37th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society
AMER INST PHYSICS. 1996: 2029–40
View details for Web of Science ID A1996UK93800032
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Stark broadening of resonance transitions in B III
PHYSICAL REVIEW A
1996; 53 (4): 2225-2229
View details for Web of Science ID A1996UE92100047
View details for PubMedID 9913131
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Line profile measurements of the 2s3s-2s3p singlet and triplet transitions in Ne VII
ASTRONOMY & ASTROPHYSICS
1996; 307 (3): 1023-1028
View details for Web of Science ID A1996UD94400039
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Spectroscopic temperature measurements of non-equilibrium plasmas
10th American-Physical-Society Topical Conference on Atomic Processes in Plasmas
AIP PRESS. 1996: 123–30
View details for Web of Science ID A1996BG55C00013
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Application of soft X-ray laser interferometry to study large-scale-length, high-density plasmas
5th International Conference on X-ray Lasers
IOP PUBLISHING LTD. 1996: 504–8
View details for Web of Science ID A1996BH42G00113
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Critical tests of line broadening theories by precision measurements
10th American-Physical-Society Topical Conference on Atomic Processes in Plasmas
AIP PRESS. 1996: 109–22
View details for Web of Science ID A1996BG55C00012
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PROFILES OF THE HE-I 2(3)P-3(3)D LINE AT HIGH-DENSITIES
JOURNAL OF QUANTITATIVE SPECTROSCOPY & RADIATIVE TRANSFER
1995; 54 (1-2): 73-80
View details for Web of Science ID A1995RL45600008
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ANALYSIS OF LITHIUMLIKE LINE SHAPES IN A GAS-LINER PINCH
12th International Conference on Spectral Line Shapes (12th ICSLS)
AIP PRESS. 1995: 153–54
View details for Web of Science ID A1995BC86N00031
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LINE BROADENING OF NONHYDROGENIC IONS IN PLASMAS
12th International Conference on Spectral Line Shapes (12th ICSLS)
AIP PRESS. 1995: 134–50
View details for Web of Science ID A1995BC86N00029
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SPECTRAL-LINE PROFILES OF N=4 TO N=5 TRANSITIONS IN C-IV, N-V AND O-VI
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
1994; 27 (22): 5507-5515
View details for Web of Science ID A1994PV22800010
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STARK-BROADENING OF SPECTRAL-LINES ALONG THE ISOELECTRONIC SEQUENCE OF B
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
1994; 27 (3): 413-422
View details for Web of Science ID A1994MX82700008
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AMPLIFICATION OF EXTREME-ULTRAVIOLET RADIATION IN A GAS-LINER PINCH PLASMA
PHYSICAL REVIEW E
1994; 49 (2): 1586-1593
View details for Web of Science ID A1994NA92100083
View details for PubMedID 9961371
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Lasing at short wavelength in a capillary discharge and in a dense Z-pinch
4th International Colloquium on X-Ray Lasers
AIP PRESS. 1994: 380–87
View details for Web of Science ID A1994BD37L00064
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INVESTIGATION OF LS COUPLING IN BORON-LIKE IONS
PHYSICAL REVIEW A
1994; 49 (1): 221-227
View details for Web of Science ID A1994MT25800029
View details for PubMedID 9910222
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PLASMA BROADENING OF NE-II-NE-VI AND F-IV-F-V SPECTRAL-LINES
PHYSICAL REVIEW E
1993; 47 (5): 3623-3630
View details for Web of Science ID A1993LF06700073
View details for PubMedID 9960417
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STARK-BROADENING OF SPECTRAL-LINES ALONG THE ISOELECTRONIC SEQUENCE OF LI
PHYSICAL REVIEW A
1992; 45 (12): 8795-8802
View details for Web of Science ID A1992JA21400058
View details for PubMedID 9906979
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INVESTIGATION OF A PAIR OF TRANSITION-PROBABILITIES OF C-III IN HIGH-DENSITY PLASMAS
PHYSICAL REVIEW A
1991; 44 (2): 1266-1269
View details for Web of Science ID A1991FY46300055
View details for PubMedID 9906076