Projects
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Rubin Observatory LSST Camera, SLAC National Accelerator Laboratory
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The Athena Wide Field Imager, Stanford University
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Dark Energy Science Collaboration (Rubin Observatory Legacy Survey of Space and Time), Stanford University
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The Dark Energy Survey, Stanford University
All Publications
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Improved noise performance from the next-generation buried-channel p-MOSFET SiSeROs
JOURNAL OF ASTRONOMICAL TELESCOPES INSTRUMENTS AND SYSTEMS
2023; 9 (2)
View details for DOI 10.1117/1.JATIS.9.2.026001
View details for Web of Science ID 001031359600016
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The Concentration-Mass relation of massive, dynamically relaxed galaxy clusters: agreement between observations and ?CDM simulations
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2023; 521 (1): 790-799
View details for DOI 10.1093/mnras/stad585
View details for Web of Science ID 000951204600041
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The Evolution and Mass Dependence of Galaxy Cluster Pressure Profiles at 0.05 <= z <= 0.60 and 4 x 10(14) M (circle dot) <= M (500) <= 30 x 10(14) M (circle dot)
ASTROPHYSICAL JOURNAL
2023; 944 (2)
View details for DOI 10.3847/1538-4357/acb33d
View details for Web of Science ID 000940666300001
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Chandra measurements of gas homogeneity and turbulence a intermediate radii in the Perseus Cluster
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2023; 518 (2): 2954-2970
View details for DOI 10.1093/mnras/stac3285
View details for Web of Science ID 000898988700027
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Reduction of cosmic-ray induced background in astronomical X-ray imaging detectors via image segmentation methods
SPIE-INT SOC OPTICAL ENGINEERING. 2023
View details for DOI 10.1117/12.2677095
View details for Web of Science ID 001259432500010
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Cosmological constraints from gas mass fractions of massive, relaxed galaxy clusters
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2022; 510 (1): 131-145
View details for DOI 10.1093/mnras/stab3390
View details for Web of Science ID 000736094100008
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X-ray speed reading with the MCRC: a low noise CCD readout ASIC enabling readout speeds of 5 Mpixel/s/channel
SPIE-INT SOC OPTICAL ENGINEERING. 2022
View details for DOI 10.1117/12.2629049
View details for Web of Science ID 000860926800057
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Reducing the background in X-ray imaging detectors via machine learning
SPIE-INT SOC OPTICAL ENGINEERING. 2022
View details for DOI 10.1117/12.2629496
View details for Web of Science ID 000865607100159
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Performance of high frame-rate X-ray CCDs for future strategic missions
SPIE-INT SOC OPTICAL ENGINEERING. 2022
View details for DOI 10.1117/12.2630139
View details for Web of Science ID 000865607100051
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Development and characterization of a fast and low noise readout for the next generation x-ray charge-coupled devices
Journal of Astronomical Telescopes, Instruments, and Systems
2022; 8 (2): 12
View details for DOI 10.1117/1.JATIS.8.2.026005
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First results on SiSeRO devices: a new x-ray detector for scientific instrumentation
Journal of Astronomical Telescopes, Instruments, and Systems
2022; 8 (2): 12
View details for DOI 10.1117/1.JATIS.8.2.026006
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Rubin observatory commissioning camera: summit integration
SPIE-INT SOC OPTICAL ENGINEERING. 2022
View details for DOI 10.1117/12.2630184
View details for Web of Science ID 000860684700013
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X-ray speed reading: enabling fast, low noise readout for next-generation CCDs
SPIE-INT SOC OPTICAL ENGINEERING. 2022
View details for DOI 10.1117/12.2630195
View details for Web of Science ID 000860926800030
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Single electron Sensitive Readout (SiSeRO) X-ray detectors: Technological progress and characterization
SPIE-INT SOC OPTICAL ENGINEERING. 2022
View details for DOI 10.1117/12.2629050
View details for Web of Science ID 000860926800021
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The history of metal enrichment traced by X-ray observations of high-redshift galaxy clusters
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2021; 507 (4): 5195-5204
View details for DOI 10.1093/mnras/stab2430
View details for Web of Science ID 000702151300034
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Spectroscopic quantification of projection effects in the SDSS redMaPPer galaxy cluster catalogue
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2021; 505 (1): 33-44
View details for DOI 10.1093/mnras/stab1243
View details for Web of Science ID 000671453100003
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Measuring H-0 using X-ray and SZ effect observations of dynamically relaxed galaxy clusters
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2021; 504 (1): 1062-1076
View details for DOI 10.1093/mnras/stab948
View details for Web of Science ID 000656137100076
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Progress toward fast, low-noise, low-power digital CCDs for Lynx and other high-energy astrophysics missions
SPIE-INT SOC OPTICAL ENGINEERING. 2021
View details for DOI 10.1117/12.2561441
View details for Web of Science ID 000674737700134
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Identifying charged particle background events in X-ray imaging detectors with novel machine learning algorithms
SPIE-INT SOC OPTICAL ENGINEERING. 2021
View details for DOI 10.1117/12.2562354
View details for Web of Science ID 000674737700039
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The environmental dependence of X-ray AGN activity at z similar to 0.4
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2020; 498 (3): 4095-4108
View details for DOI 10.1093/mnras/staa2682
View details for Web of Science ID 000587752500079
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Deep XMM-Newton observations of the most distant SPT-SZ galaxy cluster
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2020; 496 (2): 1554–64
View details for DOI 10.1093/mnras/staa1581
View details for Web of Science ID 000561118000039
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Spectroscopic confirmation of a mature galaxy cluster at a redshift of 2
NATURE
2020; 577 (7788): 39-+
Abstract
Galaxy clusters are the most massive virialized structures in the Universe and are formed through the gravitational accretion of matter over cosmic time1. The discovery2 of an evolved galaxy cluster at redshift z = 2, corresponding to a look-back time of 10.4 billion years, provides an opportunity to study its properties. The galaxy cluster XLSSC 122 was originally detected as a faint, extended X-ray source in the XMM Large Scale Structure survey and was revealed to be coincident with a compact over-density of galaxies2 with photometric redshifts of 1.9 ± 0.2. Subsequent observations3 at millimetre wavelengths detected a Sunyaev-Zel'dovich decrement along the line of sight to XLSSC 122, thus confirming the existence of hot intracluster gas, while deep imaging spectroscopy from the European Space Agency's X-ray Multi-Mirror Mission (XMM-Newton) revealed4 an extended, X-ray-bright gaseous atmosphere with a virial temperature of 60 million Kelvin, enriched with metals to the same extent as are local clusters. Here we report optical spectroscopic observations of XLSSC 122 and identify 37 member galaxies at a mean redshift of 1.98, corresponding to a look-back time of 10.4 billion years. We use photometry to determine a mean, dust-free stellar age of 2.98 billion years, indicating that star formation commenced in these galaxies at a mean redshift of 12, when the Universe was only 370 million years old. The full range of inferred formation redshifts, including the effects of dust, covers the interval from 7 to 13. These observations confirm that XLSSC 122 is a remarkably mature galaxy cluster with both evolved stellar populations in the member galaxies and a hot, metal-rich gas composing the intracluster medium.
View details for DOI 10.1038/s41586-019-1829-4
View details for Web of Science ID 000505617400022
View details for PubMedID 31894143
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Rubin commissioning camera: integration, functional testing, and lab performance
Ground-based and Airborne Instrumentation for Astronomy
2020
View details for DOI 10.1117/12.2561132
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MCRC V1: development of integrated readout electronics for next generation X-ray CCD detectors for future satellite observatories
X-Ray, Optical, and Infrared Detectors for Astronomy
2020
View details for DOI 10.1117/12.2561741
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Tiny-box: a tool for the versatile development and characterization of low noise fast x-ray imaging detectors
X-Ray, Optical, and Infrared Detectors for Astronomy
2020
View details for DOI 10.1117/12.2561826
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Ellipticity of brightest cluster galaxies as tracer of halo orientation and weak-lensing mass bias
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2019; 490 (4): 4889–97
View details for DOI 10.1093/mnras/stz2913
View details for Web of Science ID 000504000300029
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Dark Energy Surveyed Year 1 results: calibration of cluster mis-centring in the redMaPPer catalogues
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2019; 487 (2): 2578-2593
View details for DOI 10.1093/mnras/stz1361
View details for Web of Science ID 000474919700076
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Cluster Cosmology Constraints from the 2500 deg(2) SPT-SZ Survey: Inclusion of Weak Gravitational Lensing Data from Magellan and the Hubble Space Telescope
ASTROPHYSICAL JOURNAL
2019; 878 (1)
View details for DOI 10.3847/1538-4357/ab1f10
View details for Web of Science ID 000471624300004
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Dark Energy Survey Year 1 results: weak lensing mass calibration of redMaPPer galaxy clusters
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2019; 482 (1): 1352–78
View details for DOI 10.1093/mnras/sty2711
View details for Web of Science ID 000454575300095
- Improved Cosmological Constraints from SDSS redMaPPer Clusters via X-ray Follow-up of a Complete Subsample of Systems arXiv:1910.13548. 2019
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US Contributions to the Athena Wide Field Imager
SPIE-INT SOC OPTICAL ENGINEERING. 2019
View details for DOI 10.1117/12.2528532
View details for Web of Science ID 000511172300026
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Centre-excised X-ray luminosity as an efficient mass proxy for future galaxy cluster surveys
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2018; 473 (3): 3072–79
View details for DOI 10.1093/mnras/stx2554
View details for Web of Science ID 000423809400015
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The metallicity of the intracluster medium over cosmic time: further evidence for early enrichment
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2017; 472 (3): 2877–88
View details for DOI 10.1093/mnras/stx2200
View details for Web of Science ID 000413088400032
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Weighing the giants - V. Galaxy cluster scaling relations(vol 463, pg 3582, 2016)
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2017; 467 (3): 3443-3446
View details for DOI 10.1093/mnras/stx337
View details for Web of Science ID 000398419400070
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The Grism Lens-Amplified Survey from Space (GLASS). VIII. The Influence of the Cluster Properties on H alpha Emitter Galaxies at 0.3 < z < 0.7
ASTROPHYSICAL JOURNAL
2017; 837 (2)
View details for DOI 10.3847/1538-4357/aa618b
View details for Web of Science ID 000397570100003
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A series of shocks and edges in Abell 2219
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2017; 464 (3): 2896-2909
View details for DOI 10.1093/mnras/stw2384
View details for Web of Science ID 000393647600031
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Weighing the giants - V. Galaxy cluster scaling relations
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2016; 463 (4): 3582-3603
View details for DOI 10.1093/mnras/stw2250
View details for Web of Science ID 000393568200014
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Cosmology and astrophysics from relaxed galaxy clusters - V. Consistency with cold dark matter structure formation
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2016; 462 (1): 681-688
View details for DOI 10.1093/mnras/stw1707
View details for Web of Science ID 000383516700077
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Deep Chandra study of the truncated cool core of the Ophiuchus cluster
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2016; 460 (3): 2752-2764
View details for DOI 10.1093/mnras/stw1171
View details for Web of Science ID 000381204600036
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Cosmology and astrophysics from relaxed galaxy clusters - IV. Robustly calibrating hydrostatic masses with weak lensing
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2016; 457 (2): 1522-1534
View details for DOI 10.1093/mnras/stw005
View details for Web of Science ID 000373580500033
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Cosmology and astrophysics from relaxed galaxy clusters - III. Thermodynamic profiles and scaling relations
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2016; 456 (4): 4020-4039
View details for DOI 10.1093/mnras/stv2899
View details for Web of Science ID 000372265800046
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THE GRISM LENS-AMPLIFIED SURVEY FROM SPACE (GLASS). V. EXTENT AND SPATIAL DISTRIBUTION OF STAR FORMATION IN z similar to 0.5 CLUSTER GALAXIES
ASTROPHYSICAL JOURNAL
2015; 814 (2)
View details for DOI 10.1088/0004-637X/814/2/161
View details for Web of Science ID 000371463200030
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New constraints on f(R) gravity from clusters of galaxies
PHYSICAL REVIEW D
2015; 92 (4)
View details for DOI 10.1103/PhysRevD.92.044009
View details for Web of Science ID 000359118800004
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Optical and Sunyaev-Zel'dovich observations of a new sample of distant rich galaxy clusters in the ROSAT All Sky
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2015; 450 (4): 4248-4276
View details for DOI 10.1093/mnras/stv783
View details for Web of Science ID 000360824000068
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Cosmology and astrophysics from relaxed galaxy clusters - I. Sample selection
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2015; 449 (1): 199-219
View details for DOI 10.1093/mnras/stv219
View details for Web of Science ID 000355345600017
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X-ray bright active galactic nuclei in massive galaxy clusters - III. New insights into the triggering mechanisms of cluster AGN
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2015; 446 (3): 2709-2729
View details for DOI 10.1093/mnras/stu2091
View details for Web of Science ID 000350272300040
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Weighing the giants - IV. Cosmology and neutrino mass
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2015; 446 (3): 2205-2225
View details for DOI 10.1093/mnras/stu2096
View details for Web of Science ID 000350272300001
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Robust weak-lensing mass calibration of Planck galaxy clusters
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2014; 443 (3): 1973-1978
View details for DOI 10.1093/mnras/stu1423
View details for Web of Science ID 000342920400010
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Cosmology and astrophysics from relaxed galaxy clusters - II. Cosmological constraints
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2014; 440 (3): 2077-2098
View details for DOI 10.1093/mnras/stu368
View details for Web of Science ID 000334744000015
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Weighing the Giants - II. Improved calibration of photometry from stellar colours and accurate photometric redshifts
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2014; 439 (1): 28-47
View details for DOI 10.1093/mnras/stt1946
View details for Web of Science ID 000333297700023
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Weighing the Giants - III. Methods and measurements of accurate galaxy cluster weak-lensing masses
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2014; 439 (1): 48-72
View details for DOI 10.1093/mnras/stt2129
View details for Web of Science ID 000333297700024
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Weighing the Giants - I. Weak-lensing masses for 51 massive galaxy clusters: project overview, data analysis methods and cluster images
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2014; 439 (1): 2-27
View details for DOI 10.1093/mnras/stt1945
View details for Web of Science ID 000333297700022
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Azimuthally resolved X-ray spectroscopy to the edge of the Perseus Cluster
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2014; 437 (4): 3939-3961
View details for DOI 10.1093/mnras/stt2209
View details for Web of Science ID 000329177100072
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X-ray bright active galactic nuclei in massive galaxy clusters - II. The fraction of galaxies hosting active nuclei
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2014; 437 (2): 1942-1949
View details for DOI 10.1093/mnras/stt2025
View details for Web of Science ID 000331617000070
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X-ray bright active galactic nuclei in massive galaxy clusters - I. Number counts and spatial distribution
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2013; 428 (4): 3509-3525
View details for DOI 10.1093/mnras/sts288
View details for Web of Science ID 000318232000054
- Fueling X-ray AGN in the Most Massive Galaxy Clusters Half a Century of X-ray Astronomy 2012
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Baryons at the Edge of the X-ray-Brightest Galaxy Cluster
SCIENCE
2011; 331 (6024): 1576-1579
Abstract
Studies of the diffuse x-ray-emitting gas in galaxy clusters have provided powerful constraints on cosmological parameters and insights into plasma astrophysics. However, measurements of the faint cluster outskirts have become possible only recently. Using data from the Suzaku x-ray telescope, we determined an accurate, spatially resolved census of the gas, metals, and dark matter out to the edge of the Perseus Cluster. Contrary to previous results, our measurements of the cluster baryon fraction are consistent with the expected universal value at half of the virial radius. The apparent baryon fraction exceeds the cosmic mean at larger radii, suggesting a clumpy distribution of the gas, which is important for understanding the ongoing growth of clusters from the surrounding cosmic web.
View details for DOI 10.1126/science.1200331
View details for PubMedID 21436446
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Extreme active galactic nucleus feedback and cool-core destruction in the X-ray luminous galaxy cluster MACS J1931.8-2634
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2011; 411 (3): 1641-1658
View details for DOI 10.1111/j.1365-2966.2010.17801.x
View details for Web of Science ID 000287486400018
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CONSTRAINING DARK ENERGY AND GRAVITY WITH X-RAY GALAXY CLUSTERS
7th International Heidelberg Conference on Dark Matter in Astrophysics and Particle Physics (DARK 2009)
WORLD SCIENTIFIC PUBL CO PTE LTD. 2010: 426–439
View details for Web of Science ID 000278563100034
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CONSTRAINING GRAVITY AT LARGE SCALES WITH X-RAY GALAXY CLUSTER STUDIES
Conference on Dark Energy, Dark Matter - Observation, Experiments and Theories
E D P SCIENCES. 2009: 149–151
View details for DOI 10.1051/eas/0936021
View details for Web of Science ID 000269211400021
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REVEALING THE PROPERTIES OF DARK MATTER IN THE MERGING CLUSTER MACS J0025.4-1222
ASTROPHYSICAL JOURNAL
2008; 687 (2): 959-967
View details for Web of Science ID 000260566700015
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Cool X-ray emitting gas in the core of the Centaurus cluster of galaxies
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2008; 385 (3): 1186-1200
View details for DOI 10.1111/j.1365-2966.2008.12952.x
View details for Web of Science ID 000254604600007
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Improved constraints on dark energy from Chandra X-ray observations of the largest relaxed galaxy clusters
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2008; 383 (3): 879-896
View details for DOI 10.1111/j.1365-2966.2007.12610.x
View details for Web of Science ID 000252851500006
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Tracing gas motions in the Centaurus cluster
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2006; 368 (3): 1369-1376
View details for DOI 10.1111/j.1365-2966.2006.10218.x
View details for Web of Science ID 000237353000033
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An XMM-Newton observation of Abell 2597
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2005; 358 (2): 585-600
View details for DOI 10.1111/j.1365-2966.2005.08822.x
View details for Web of Science ID 000227673700021
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The galaxy cluster Abell 3581 as seen by Chandra
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2005; 356 (1): 237-246
View details for DOI 10.1111/j.1365-2966.2004.08445.x
View details for Web of Science ID 000225749300021
- An XMM-Newton observation of Abell 259 COSPAR Scientific Assembly 2004
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Some effects of small-scale metallicity variations in cooling flows
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2003; 338 (4): 824-836
View details for Web of Science ID 000180607900004
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On conduction, cooling flows and galaxy formation
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2002; 335 (3): L71-L74
View details for DOI 10.1046/j.1365-8711.2002.05884.x
View details for Web of Science ID 000178283100005
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The missing soft X-ray luminosity in cluster cooling flows
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
2002; 332 (3): L50-L54
View details for Web of Science ID 000175664400002
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Inhomogeneous metallicities and cluster cooling flows
ASTRONOMICAL SOC PACIFIC. 2002: 85-90
View details for Web of Science ID 000176731700009