Persis Drell
Provost, Emerita, James and Anna Marie Spilker Professor, Professor of Materials Science and Engineering and of Physics
Bio
Persis Drell is the James and Anna Marie Spilker Professor in the School of Engineering, a professor of materials science and engineering, and a professor of physics. From Feb 1, 2017 to Sept. 30, 2023, Drell was the provost of Stanford University.
Prior to her appointment as provost in February 2017, she was dean of the Stanford School of Engineering from 2014 to 2017 and director of U.S. Department of Energy SLAC National Acceleratory Laboratory from 2007 to 2012.
She earned her bachelor’s degree in mathematics and physics from Wellesley College and her PhD in atomic physics from UC Berkeley. Before joining the faculty at Stanford in 2002, she was a faculty member in the physics department at Cornell University for 14 years.
2024-25 Courses
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Independent Studies (3)
- Independent Research and Study
PHYSICS 190 (Aut, Win, Spr, Sum) - Research
PHYSICS 490 (Aut, Win, Spr, Sum) - Senior Thesis Research
PHYSICS 205 (Aut, Win, Spr, Sum)
- Independent Research and Study
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Prior Year Courses
2023-24 Courses
- Why College? Your Education and the Good Life
COLLEGE 101 (Aut)
2022-23 Courses
- Why College? Your Education and the Good Life
COLLEGE 101 (Aut)
- Why College? Your Education and the Good Life
All Publications
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Search for Cosmic-Ray Electron and Positron Anisotropies with Seven Years of Fermi Large Area Telescope Data
PHYSICAL REVIEW LETTERS
2017; 118 (9)
Abstract
The Large Area Telescope on board the Fermi Gamma-ray Space Telescope has collected the largest ever sample of high-energy cosmic-ray electron and positron events since the beginning of its operation. Potential anisotropies in the arrival directions of cosmic-ray electrons or positrons could be a signature of the presence of nearby sources. We use almost seven years of data with energies above 42 GeV processed with the Pass 8 reconstruction. The present data sample can probe dipole anisotropies down to a level of 10^{-3}. We take into account systematic effects that could mimic true anisotropies at this level. We present a detailed study of the event selection optimization of the cosmic-ray electrons and positrons to be used for anisotropy searches. Since no significant anisotropies have been detected on any angular scale, we present upper limits on the dipole anisotropy. The present constraints are among the strongest to date probing the presence of nearby young and middle-aged sources.
View details for DOI 10.1103/PhysRevLett.118.091103
View details for PubMedID 28306280
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Gamma-Ray Blazars within the First 2 Billion Years
ASTROPHYSICAL JOURNAL LETTERS
2017; 837 (1)
View details for DOI 10.3847/2041-8213/aa5fff
View details for Web of Science ID 000401605500005
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SEARCHING THE GAMMA-RAY SKY FOR COUNTERPARTS TO GRAVITATIONAL WAVE SOURCES: FERMI GAMMA-RAY BURST MONITOR. AND LARGE AREA TELESCOPE OBSERVATIONS OF LVT151012 AND GW151226
ASTROPHYSICAL JOURNAL
2017; 835 (1)
View details for DOI 10.3847/1538-4357/835/1/82
View details for Web of Science ID 000393455400082
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SUPPLEMENT: "LOCALIZATION AND BROADBAND FOLLOW-UP OF THE GRAVITATIONAL-WAVE TRANSIENT GW150914" (2016, ApJL, 826, L13)
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
2016; 225 (1)
View details for DOI 10.3847/0067-0049/225/1/8
View details for Web of Science ID 000382309000008
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MINUTE-TIMESCALE > 100 MeV gamma-RAY VARIABILITY DURING THE GIANT OUTBURST OF QUASAR 3C 279 OBSERVED BY FERMI-LAT IN 2015 JUNE
ASTROPHYSICAL JOURNAL LETTERS
2016; 824 (2)
View details for DOI 10.3847/2041-8205/824/2/L20
View details for Web of Science ID 000378168200004
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FERMI-LAT OBSERVATIONS OF THE LIGO EVENT GW150914
ASTROPHYSICAL JOURNAL LETTERS
2016; 823 (1)
View details for DOI 10.3847/2041-8205/823/1/L2
View details for Web of Science ID 000376391700002
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FERMI LAT STACKING ANALYSIS OF SWIFT LOCALIZED GRBs
ASTROPHYSICAL JOURNAL
2016; 822 (2)
View details for DOI 10.3847/0004-637X/822/2/68
View details for Web of Science ID 000377204900011
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THE FIRST FERMI LAT SUPERNOVA REMNANT CATALOG
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
2016; 224 (1)
View details for DOI 10.3847/0067-0049/224/1/8
View details for Web of Science ID 000377050200008
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Search for Spectral Irregularities due to Photon-Axionlike-Particle Oscillations with the Fermi Large Area Telescope
PHYSICAL REVIEW LETTERS
2016; 116 (16)
Abstract
We report on the search for spectral irregularities induced by oscillations between photons and axionlike-particles (ALPs) in the γ-ray spectrum of NGC 1275, the central galaxy of the Perseus cluster. Using 6 years of Fermi Large Area Telescope data, we find no evidence for ALPs and exclude couplings above 5×10^{-12} GeV^{-1} for ALP masses 0.5≲m_{a}≲5 neV at 95% confidence. The limits are competitive with the sensitivity of planned laboratory experiments, and, together with other bounds, strongly constrain the possibility that ALPs can reduce the γ-ray opacity of the Universe.
View details for DOI 10.1103/PhysRevLett.116.161101
View details for Web of Science ID 000374559300002
View details for PubMedID 27152783
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Resolving the Extragalactic gamma-Ray Background above 50 GeV with the Fermi Large Area Telescope
PHYSICAL REVIEW LETTERS
2016; 116 (15)
Abstract
The Fermi Large Area Telescope (LAT) Collaboration has recently released a catalog of 360 sources detected above 50 GeV (2FHL). This catalog was obtained using 80 months of data re-processed with Pass 8, the newest event-level analysis, which significantly improves the acceptance and angular resolution of the instrument. Most of the 2FHL sources at high Galactic latitude are blazars. Using detailed Monte Carlo simulations, we measure, for the first time, the source count distribution, dN/dS, of extragalactic γ-ray sources at E>50 GeV and find that it is compatible with a Euclidean distribution down to the lowest measured source flux in the 2FHL (∼8×10^{-12} ph cm^{-2} s^{-1}). We employ a one-point photon fluctuation analysis to constrain the behavior of dN/dS below the source detection threshold. Overall, the source count distribution is constrained over three decades in flux and found compatible with a broken power law with a break flux, S_{b}, in the range [8×10^{-12},1.5×10^{-11}] ph cm^{-2} s^{-1} and power-law indices below and above the break of α_{2}∈[1.60,1.75] and α_{1}=2.49±0.12, respectively. Integration of dN/dS shows that point sources account for at least 86_{-14}^{+16}% of the total extragalactic γ-ray background. The simple form of the derived source count distribution is consistent with a single population (i.e., blazars) dominating the source counts to the minimum flux explored by this analysis. We estimate the density of sources detectable in blind surveys that will be performed in the coming years by the Cherenkov Telescope Array.
View details for DOI 10.1103/PhysRevLett.116.151105
View details for PubMedID 27127954
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Measurement of the high-energy gamma-ray emission from the Moon with the Fermi Large Area Telescope
PHYSICAL REVIEW D
2016; 93 (8)
View details for DOI 10.1103/PhysRevD.93.082001
View details for Web of Science ID 000373584900002
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DEVELOPMENT OF THE MODEL OF GALACTIC INTERSTELLAR EMISSION FOR STANDARD POINT-SOURCE ANALYSIS OF FERMI LARGE AREA TELESCOPE DATA
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
2016; 223 (2)
View details for DOI 10.3847/0067-0049/223/2/26
View details for Web of Science ID 000375304600008
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CONTEMPORANEOUS BROADBAND OBSERVATIONS OF THREE HIGH-REDSHIFT BL LAC OBJECTS
ASTROPHYSICAL JOURNAL
2016; 820 (1)
View details for DOI 10.3847/0004-637X/820/1/72
View details for Web of Science ID 000372787000071
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SEARCH FOR GAMMA-RAY EMISSION FROM THE COMA CLUSTER WITH SIX YEARS OF FERMI-LAT DATA
ASTROPHYSICAL JOURNAL
2016; 819 (2)
View details for DOI 10.3847/0004-637X/819/2/149
View details for Web of Science ID 000372305700061
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DEEP MORPHOLOGICAL AND SPECTRAL STUDY OF THE SNR RCW 86 WITH FERMI-LAT
ASTROPHYSICAL JOURNAL
2016; 819 (2)
View details for DOI 10.3847/0004-637X/819/2/98
View details for Web of Science ID 000372305700010
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FERMI-LAT OBSERVATIONS OF HIGH-ENERGY gamma-RAY EMISSION TOWARD THE GALACTIC CENTER
ASTROPHYSICAL JOURNAL
2016; 819 (1)
View details for DOI 10.3847/0004-637X/819/1/44
View details for Web of Science ID 000372303400044
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Deep view of the Large Magellanic Cloud with six years of Fermi-LAT observations
ASTRONOMY & ASTROPHYSICS
2016; 586
View details for DOI 10.1051/0004-6361/201526920
View details for Web of Science ID 000369715900082
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2FHL: THE SECOND CATALOG OF HARD FERMI-LAT SOURCES
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
2016; 222 (1)
View details for DOI 10.3847/0067-0049/222/1/5
View details for Web of Science ID 000368982300005
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Searching for Dark Matter Annihilation from Milky Way Dwarf Spheroidal Galaxies with Six Years of Fermi Large Area Telescope Data
PHYSICAL REVIEW LETTERS
2015; 115 (23)
Abstract
The dwarf spheroidal satellite galaxies (dSphs) of the Milky Way are some of the most dark matter (DM) dominated objects known. We report on γ-ray observations of Milky Way dSphs based on six years of Fermi Large Area Telescope data processed with the new Pass8 event-level analysis. None of the dSphs are significantly detected in γ rays, and we present upper limits on the DM annihilation cross section from a combined analysis of 15 dSphs. These constraints are among the strongest and most robust to date and lie below the canonical thermal relic cross section for DM of mass ≲100 GeV annihilating via quark and τ-lepton channels.
View details for DOI 10.1103/PhysRevLett.115.231301
View details for PubMedID 26684107
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An extremely bright gamma-ray pulsar in the Large Magellanic Cloud
SCIENCE
2015; 350 (6262): 801-805
Abstract
Pulsars are rapidly spinning, highly magnetized neutron stars, created in the gravitational collapse of massive stars. We report the detection of pulsed giga-electron volt gamma rays from the young pulsar PSR J0540-6919 in the Large Magellanic Cloud, a satellite galaxy of the Milky Way. This is the first gamma-ray pulsar detected in another galaxy. It has the most luminous pulsed gamma-ray emission yet observed, exceeding the Crab pulsar's by a factor of 20. PSR J0540-6919 presents an extreme test case for understanding the structure and evolution of neutron star magnetospheres.
View details for DOI 10.1126/science.aac7400
View details for Web of Science ID 000364897000041
View details for PubMedID 26564852
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MULTIWAVELENGTH EVIDENCE FOR QUASI-PERIODIC MODULATION IN THE GAMMA-RAY BLAZAR PG 1553+113
ASTROPHYSICAL JOURNAL LETTERS
2015; 813 (2)
View details for DOI 10.1088/2041-8205/813/2/L41
View details for Web of Science ID 000365035000019
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SEARCH FOR EXTENDED GAMMA-RAY EMISSION FROM THE VIRGO GALAXY CLUSTER WITH FERMI-LAT
ASTROPHYSICAL JOURNAL
2015; 812 (2)
View details for DOI 10.1088/0004-637X/812/2/159
View details for Web of Science ID 000365206600071
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THE THIRD CATALOG OF ACTIVE GALACTIC NUCLEI DETECTED BY THE FERMI LARGE AREA TELESCOPE
ASTROPHYSICAL JOURNAL
2015; 810 (1)
View details for DOI 10.1088/0004-637X/810/1/14
View details for Web of Science ID 000361800900014
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Limits on dark matter annihilation signals from the Fermi LAT 4-year measurement of the isotropic gamma-ray background
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
2015
View details for DOI 10.1088/1475-7516/2015/09/008
View details for Web of Science ID 000365690000008
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PSR J1906+0722: AN ELUSIVE GAMMA-RAY PULSAR
ASTROPHYSICAL JOURNAL LETTERS
2015; 809 (1)
View details for DOI 10.1088/2041-8205/809/1/L2
View details for Web of Science ID 000359321900002
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SEARCH FOR EARLY GAMMA-RAY PRODUCTION IN SUPERNOVAE LOCATED IN A DENSE CIRCUMSTELLAR MEDIUM WITH THE FERMI LAT
ASTROPHYSICAL JOURNAL
2015; 807 (2)
View details for DOI 10.1088/0004-637X/807/2/169
View details for Web of Science ID 000358967000055
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The linac coherent light source single particle imaging road map
STRUCTURAL DYNAMICS
2015; 2 (4)
Abstract
Intense femtosecond x-ray pulses from free-electron laser sources allow the imaging of individual particles in a single shot. Early experiments at the Linac Coherent Light Source (LCLS) have led to rapid progress in the field and, so far, coherent diffractive images have been recorded from biological specimens, aerosols, and quantum systems with a few-tens-of-nanometers resolution. In March 2014, LCLS held a workshop to discuss the scientific and technical challenges for reaching the ultimate goal of atomic resolution with single-shot coherent diffractive imaging. This paper summarizes the workshop findings and presents the roadmap toward reaching atomic resolution, 3D imaging at free-electron laser sources.
View details for DOI 10.1063/1.4918726
View details for Web of Science ID 000360649200003
View details for PubMedCentralID PMC4711616
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Updated search for spectral lines from Galactic dark matter interactions with pass 8 data from the Fermi Large Area Telescope
PHYSICAL REVIEW D
2015; 91 (12)
View details for DOI 10.1103/PhysRevD.91.122002
View details for Web of Science ID 000356583600002
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SECOND CATALOG OF ACTIVE GALACTIC NUCLEI DETECTED BY THE FERMI LARGE AREA TELESCOPE (vol 743, 171, 2011)
ASTROPHYSICAL JOURNAL
2015; 806 (1)
View details for DOI 10.1088/0004-637X/806/1/144
View details for Web of Science ID 000356810300144
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FERMI LARGE AREA TELESCOPE THIRD SOURCE CATALOG
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
2015; 218 (2)
View details for DOI 10.1088/0067-0049/218/2/23
View details for Web of Science ID 000357122200009
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GAMMA-RAY FLARING ACTIVITY FROM THE GRAVITATIONALLY LENSED BLAZAR PKS 1830-211 OBSERVED BY Fermi LAT
ASTROPHYSICAL JOURNAL
2015; 799 (2)
View details for DOI 10.1088/0004-637X/799/2/143
View details for Web of Science ID 000348820900030
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THE SPECTRUM OF ISOTROPIC DIFFUSE GAMMA-RAY EMISSION BETWEEN 100 MeV AND 820 GeV
ASTROPHYSICAL JOURNAL
2015; 799 (1)
View details for DOI 10.1088/0004-637X/799/1/86
View details for Web of Science ID 000348214500084
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THE SPECTRUM AND MORPHOLOGY OF THE FERMI BUBBLES
ASTROPHYSICAL JOURNAL
2014; 793 (1)
View details for DOI 10.1088/0004-637X/793/1/64
View details for Web of Science ID 000341301700064
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Fermi establishes classical novae as a distinct class of gamma-ray sources
SCIENCE
2014; 345 (6196): 554-558
View details for DOI 10.1126/science.1253947
View details for Web of Science ID 000339651300043
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IMPULSIVE AND LONG DURATION HIGH-ENERGY GAMMA-RAY EMISSION FROM THE VERY BRIGHT 2012 MARCH 7 SOLAR FLARES
ASTROPHYSICAL JOURNAL
2014; 789 (1)
View details for DOI 10.1088/0004-637X/789/1/20
View details for Web of Science ID 000338103400020
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HIGH-ENERGY GAMMA-RAY EMISSION FROM SOLAR FLARES: SUMMARY OF FERMI LARGE AREA TELESCOPE DETECTIONS AND ANALYSIS OF TWO M-CLASS FLARES
ASTROPHYSICAL JOURNAL
2014; 787 (1)
View details for DOI 10.1088/0004-637X/787/1/15
View details for Web of Science ID 000335924200015
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SEARCH FOR COSMIC-RAY-INDUCED GAMMA-RAY EMISSION IN GALAXY CLUSTERS
ASTROPHYSICAL JOURNAL
2014; 787 (1)
View details for DOI 10.1088/0004-637X/787/1/18
View details for Web of Science ID 000335924200018
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MULTIFREQUENCY STUDIES OF THE PECULIAR QUASAR 4C+21.35 DURING THE 2010 FLARING ACTIVITY
ASTROPHYSICAL JOURNAL
2014; 786 (2)
View details for DOI 10.1088/0004-637X/786/2/157
View details for Web of Science ID 000335884500080
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Inferred Cosmic-Ray Spectrum from Fermi Large Area Telescope gamma-Ray Observations of Earth's Limb
PHYSICAL REVIEW LETTERS
2014; 112 (15)
Abstract
Recent accurate measurements of cosmic-ray (CR) species by ATIC-2, CREAM, and PAMELA reveal an unexpected hardening in the proton and He spectra above a few hundred GeV, a gradual softening of the spectra just below a few hundred GeV, and a harder spectrum of He compared to that of protons. These newly discovered features may offer a clue to the origin of high-energy CRs. We use the Fermi Large Area Telescope observations of the γ-ray emission from Earth's limb for an indirect measurement of the local spectrum of CR protons in the energy range ∼90 GeV-6 TeV (derived from a photon energy range 15 GeV-1 TeV). Our analysis shows that single power law and broken power law spectra fit the data equally well and yield a proton spectrum with index 2.68±0.04 and 2.61±0.08 above ∼200 GeV, respectively.
View details for DOI 10.1103/PhysRevLett.112.151103
View details for Web of Science ID 000334597300003
View details for PubMedID 24785023
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DEEP BROADBAND OBSERVATIONS OF THE DISTANT GAMMA-RAY BLAZAR PKS 1424+240
ASTROPHYSICAL JOURNAL LETTERS
2014; 785 (1)
View details for DOI 10.1088/2041-8205/785/1/L16
View details for Web of Science ID 000334345000016
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Fermi LARGE AREA TELESCOPE OBSERVATIONS OF BLAZAR 3C 279 OCCULTATIONS BY THE SUN
ASTROPHYSICAL JOURNAL
2014; 784 (2)
View details for DOI 10.1088/0004-637X/784/2/118
View details for Web of Science ID 000335519400033
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Dark matter constraints from observations of 25 Milky Way satellite galaxies with the Fermi Large Area Telescope
PHYSICAL REVIEW D
2014; 89 (4)
View details for DOI 10.1103/PhysRevD.89.042001
View details for Web of Science ID 000339630400001
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The First Pulse of the Extremely Bright GRB 130427A: A Test Lab for Synchrotron Shocks
SCIENCE
2014; 343 (6166): 51-54
Abstract
Gamma-ray burst (GRB) 130427A is one of the most energetic GRBs ever observed. The initial pulse up to 2.5 seconds is possibly the brightest well-isolated pulse observed to date. A fine time resolution spectral analysis shows power-law decays of the peak energy from the onset of the pulse, consistent with models of internal synchrotron shock pulses. However, a strongly correlated power-law behavior is observed between the luminosity and the spectral peak energy that is inconsistent with curvature effects arising in the relativistic outflow. It is difficult for any of the existing models to account for all of the observed spectral and temporal behaviors simultaneously.
View details for DOI 10.1126/science.1242302
View details for Web of Science ID 000329162000044
View details for PubMedID 24263132
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Fermi-LAT Observations of the Gamma-Ray Burst GRB 130427A
SCIENCE
2014; 343 (6166): 42-47
Abstract
The observations of the exceptionally bright gamma-ray burst (GRB) 130427A by the Large Area Telescope aboard the Fermi Gamma-ray Space Telescope provide constraints on the nature of these unique astrophysical sources. GRB 130427A had the largest fluence, highest-energy photon (95 GeV), longest γ-ray duration (20 hours), and one of the largest isotropic energy releases ever observed from a GRB. Temporal and spectral analyses of GRB 130427A challenge the widely accepted model that the nonthermal high-energy emission in the afterglow phase of GRBs is synchrotron emission radiated by electrons accelerated at an external shock.
View details for DOI 10.1126/science.1242353
View details for Web of Science ID 000329162000042
View details for PubMedID 24263133
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THE FIRST FERMI-LAT CATALOG OF SOURCES ABOVE 10 GeV
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
2013; 209 (2)
View details for DOI 10.1088/0067-0049/209/2/34
View details for Web of Science ID 000328059500016
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FERMI LARGE AREA TELESCOPE STUDY OF COSMIC-RAYS AND THE INTERSTELLAR MEDIUM IN NEARBY MOLECULAR CLOUDS (vol 755, 22, 2012)
ASTROPHYSICAL JOURNAL
2013; 778 (1)
View details for DOI 10.1088/0004-637X/778/1/82
View details for Web of Science ID 000327131700082
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THE FIRST FERMI-LAT GAMMA-RAY BURST CATALOG
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
2013; 209 (1)
View details for DOI 10.1088/0067-0049/209/1/11
View details for Web of Science ID 000326571000011
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PSR J2021+4026 IN THE GAMMA CYGNI REGION: THE FIRST VARIABLE gamma-RAY PULSAR SEEN BY THE Fermi LAT
ASTROPHYSICAL JOURNAL LETTERS
2013; 777 (1)
View details for DOI 10.1088/2041-8205/777/1/L2
View details for Web of Science ID 000326187400002
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Search for gamma-ray spectral lines with the Fermi Large Area Telescope and dark matter implications
PHYSICAL REVIEW D
2013; 88 (8)
View details for DOI 10.1103/PhysRevD.88.082002
View details for Web of Science ID 000326107300001
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THE SECOND FERMI LARGE AREA TELESCOPE CATALOG OF GAMMA-RAY PULSARS
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
2013; 208 (2)
View details for DOI 10.1088/0067-0049/208/2/17
View details for Web of Science ID 000325276600004
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ASSOCIATING LONG-TERM gamma-RAY VARIABILITY WITH THE SUPERORBITAL PERIOD OF LS I+61 degrees 303
ASTROPHYSICAL JOURNAL LETTERS
2013; 773 (2)
View details for DOI 10.1088/2041-8205/773/2/L35
View details for Web of Science ID 000322899600018
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CONSTRAINTS ON THE GALACTIC POPULATION OF TeV PULSAR WIND NEBULAE USING FERMI LARGE AREA TELESCOPE OBSERVATIONS
ASTROPHYSICAL JOURNAL
2013; 773 (1)
View details for DOI 10.1088/0004-637X/773/1/77
View details for Web of Science ID 000322531900077
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CONSTRAINTS ON THE COSMIC-RAY DENSITY GRADIENT BEYOND THE SOLAR CIRCLE FROM FERMI gamma-RAY OBSERVATIONS OF THE THIRD GALACTIC QUADRANT (vol 726, pg 81, 2011)
ASTROPHYSICAL JOURNAL
2013; 772 (2)
View details for DOI 10.1088/0004-637X/772/2/154
View details for Web of Science ID 000322024700076
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THE FERMI ALL-SKY VARIABILITY ANALYSIS: A LIST OF FLARING GAMMA-RAY SOURCES AND THE SEARCH FOR TRANSIENTS IN OUR GALAXY
ASTROPHYSICAL JOURNAL
2013; 771 (1)
View details for DOI 10.1088/0004-637X/771/1/57
View details for Web of Science ID 000321274200057
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Detection of the Characteristic Pion-Decay Signature in Supernova Remnants
SCIENCE
2013; 339 (6121): 807-811
Abstract
Cosmic rays are particles (mostly protons) accelerated to relativistic speeds. Despite wide agreement that supernova remnants (SNRs) are the sources of galactic cosmic rays, unequivocal evidence for the acceleration of protons in these objects is still lacking. When accelerated protons encounter interstellar material, they produce neutral pions, which in turn decay into gamma rays. This offers a compelling way to detect the acceleration sites of protons. The identification of pion-decay gamma rays has been difficult because high-energy electrons also produce gamma rays via bremsstrahlung and inverse Compton scattering. We detected the characteristic pion-decay feature in the gamma-ray spectra of two SNRs, IC 443 and W44, with the Fermi Large Area Telescope. This detection provides direct evidence that cosmic-ray protons are accelerated in SNRs.
View details for DOI 10.1126/science.1231160
View details for Web of Science ID 000314874400045
View details for PubMedID 23413352
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MULTIWAVELENGTH OBSERVATIONS OF GRB 110731A: GeV EMISSION FROM ONSET TO AFTERGLOW
ASTROPHYSICAL JOURNAL
2013; 763 (2)
View details for DOI 10.1088/0004-637X/763/2/71
View details for Web of Science ID 000313869800002
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CONSTRAINTS ON THE GALACTIC HALO DARK MATTER FROM FERMI-LAT DIFFUSE MEASUREMENTS
ASTROPHYSICAL JOURNAL
2012; 761 (2)
View details for DOI 10.1088/0004-637X/761/2/91
View details for Web of Science ID 000312090300010
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Binary Millisecond Pulsar Discovery via Gamma-Ray Pulsations
SCIENCE
2012; 338 (6112): 1314-1317
Abstract
Millisecond pulsars, old neutron stars spun up by accreting matter from a companion star, can reach high rotation rates of hundreds of revolutions per second. Until now, all such "recycled" rotation-powered pulsars have been detected by their spin-modulated radio emission. In a computing-intensive blind search of gamma-ray data from the Fermi Large Area Telescope (with partial constraints from optical data), we detected a 2.5-millisecond pulsar, PSR J1311-3430. This unambiguously explains a formerly unidentified gamma-ray source that had been a decade-long enigma, confirming previous conjectures. The pulsar is in a circular orbit with an orbital period of only 93 minutes, the shortest of any spin-powered pulsar binary ever found.
View details for DOI 10.1126/science.1229054
View details for Web of Science ID 000311991200058
View details for PubMedID 23112297
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The Imprint of the Extragalactic Background Light in the Gamma-Ray Spectra of Blazars
SCIENCE
2012; 338 (6111): 1190-1192
Abstract
The light emitted by stars and accreting compact objects through the history of the universe is encoded in the intensity of the extragalactic background light (EBL). Knowledge of the EBL is important to understand the nature of star formation and galaxy evolution, but direct measurements of the EBL are limited by galactic and other foreground emissions. Here, we report an absorption feature seen in the combined spectra of a sample of gamma-ray blazars out to a redshift of z ∼ 1.6. This feature is caused by attenuation of gamma rays by the EBL at optical to ultraviolet frequencies and allowed us to measure the EBL flux density in this frequency band.
View details for DOI 10.1126/science.1227160
View details for Web of Science ID 000311666200040
View details for PubMedID 23118013
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THE FERMI LARGE AREA TELESCOPE ON ORBIT: EVENT CLASSIFICATION, INSTRUMENT RESPONSE FUNCTIONS, AND CALIBRATION
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
2012; 203 (1)
View details for DOI 10.1088/0067-0049/203/1/4
View details for Web of Science ID 000310908300004
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FERMI OBSERVATIONS OF gamma-RAY EMISSION FROM THE MOON
ASTROPHYSICAL JOURNAL
2012; 758 (2)
View details for DOI 10.1088/0004-637X/758/2/140
View details for Web of Science ID 000310562000069
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GRB110721A: AN EXTREME PEAK ENERGY AND SIGNATURES OF THE PHOTOSPHERE
ASTROPHYSICAL JOURNAL LETTERS
2012; 757 (2)
View details for DOI 10.1088/2041-8205/757/2/L31
View details for Web of Science ID 000308921700012
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GAMMA-RAY OBSERVATIONS OF THE ORION MOLECULAR CLOUDS WITH THE FERMI LARGE AREA TELESCOPE
ASTROPHYSICAL JOURNAL
2012; 756 (1)
View details for DOI 10.1088/0004-637X/756/1/4
View details for Web of Science ID 000309044300004
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GeV OBSERVATIONS OF STAR-FORMING GALAXIES WITH THE FERMI LARGE AREA TELESCOPE
ASTROPHYSICAL JOURNAL
2012; 755 (2)
View details for DOI 10.1088/0004-637X/755/2/164
View details for Web of Science ID 000307791400081
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FERMI LARGE AREA TELESCOPE STUDY OF COSMIC RAYS AND THE INTERSTELLAR MEDIUM IN NEARBY MOLECULAR CLOUDS
ASTROPHYSICAL JOURNAL
2012; 755 (1)
View details for DOI 10.1088/0004-637X/755/1/22
View details for Web of Science ID 000306909500022
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CONSTRAINING THE HIGH-ENERGY EMISSION FROM GAMMA-RAY BURSTS WITH FERMI
ASTROPHYSICAL JOURNAL
2012; 754 (2)
View details for DOI 10.1088/0004-637X/754/2/121
View details for Web of Science ID 000306666700042
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Fermi LAT search for dark matter in gamma-ray lines and the inclusive photon spectrum
PHYSICAL REVIEW D
2012; 86 (2)
View details for DOI 10.1103/PhysRevD.86.022002
View details for Web of Science ID 000306193000001
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A STATISTICAL APPROACH TO RECOGNIZING SOURCE CLASSES FOR UNASSOCIATED SOURCES IN THE FIRST FERMI-LAT CATALOG
ASTROPHYSICAL JOURNAL
2012; 753 (1)
View details for DOI 10.1088/0004-637X/753/1/83
View details for Web of Science ID 000305632500083
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MULTI-WAVELENGTH OBSERVATIONS OF BLAZAR AO 0235+164 IN THE 2008-2009 FLARING STATE
ASTROPHYSICAL JOURNAL
2012; 751 (2)
View details for DOI 10.1088/0004-637X/751/2/159
View details for Web of Science ID 000304204600080
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What defines a healthy US particle-physics program?
PHYSICS TODAY
2012; 65 (6): 8-9
View details for Web of Science ID 000305099700001
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Anisotropies in the diffuse gamma-ray background measured by the Fermi LAT (vol 85, 083007, 2012)
PHYSICAL REVIEW D
2012; 85 (10)
View details for DOI 10.1103/PhysRevD.85.109901
View details for Web of Science ID 000304067000007
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FERMI-LAT OBSERVATIONS OF THE DIFFUSE gamma-RAY EMISSION: IMPLICATIONS FORCOSMIC RAYS AND THE INTERSTELLAR MEDIUM
ASTROPHYSICAL JOURNAL
2012; 750 (1)
View details for DOI 10.1088/0004-637X/750/1/3
View details for Web of Science ID 000303063500003
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Anisotropies in the diffuse gamma-ray background measured by the Fermi LAT
PHYSICAL REVIEW D
2012; 85 (8)
View details for DOI 10.1103/PhysRevD.85.083007
View details for Web of Science ID 000303170000001
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FERMI DETECTION OF gamma-RAY EMISSION FROM THE M2 SOFT X-RAY FLARE ON 2010 JUNE 12 (vol 745, pg 144,2012)
ASTROPHYSICAL JOURNAL
2012; 748 (2)
View details for DOI 10.1088/0004-637X/748/2/151
View details for Web of Science ID 000302135200079
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FERMI LARGE AREA TELESCOPE SECOND SOURCE CATALOG
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
2012; 199 (2)
View details for DOI 10.1088/0067-0049/199/2/31
View details for Web of Science ID 000303105400007
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SEARCH FOR DARK MATTER SATELLITES USING FERMI-LAT
ASTROPHYSICAL JOURNAL
2012; 747 (2)
View details for DOI 10.1088/0004-637X/747/2/121
View details for Web of Science ID 000302856400037
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SEARCH FOR GAMMA-RAY EMISSION FROM X-RAY-SELECTED SEYFERT GALAXIES WITH FERMI-LAT
ASTROPHYSICAL JOURNAL
2012; 747 (2)
View details for DOI 10.1088/0004-637X/747/2/104
View details for Web of Science ID 000302856400020
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Limits on large extra dimensions based on observations of neutron stars with the Fermi-LAT
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
2012
View details for DOI 10.1088/1475-7516/2012/02/012
View details for Web of Science ID 000301176000013
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FERMI DETECTION OF gamma-RAY EMISSION FROM THE M2 SOFT X-RAY FLARE ON 2010 JUNE 12f
ASTROPHYSICAL JOURNAL
2012; 745 (2)
View details for DOI 10.1088/0004-637X/745/2/144
View details for Web of Science ID 000300326800042
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The cosmic-ray and gas content of the Cygnus region as measured in gamma-rays by the Fermi Large Area Telescope
ASTRONOMY & ASTROPHYSICS
2012; 538
View details for DOI 10.1051/0004-6361/201117539
View details for Web of Science ID 000300614100071
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Periodic Emission from the Gamma-Ray Binary 1FGL J1018.6-5856
SCIENCE
2012; 335 (6065): 189-193
Abstract
Gamma-ray binaries are stellar systems containing a neutron star or black hole, with gamma-ray emission produced by an interaction between the components. These systems are rare, even though binary evolution models predict dozens in our Galaxy. A search for gamma-ray binaries with the Fermi Large Area Telescope (LAT) shows that 1FGL J1018.6-5856 exhibits intensity and spectral modulation with a 16.6-day period. We identified a variable x-ray counterpart, which shows a sharp maximum coinciding with maximum gamma-ray emission, as well as an O6V((f)) star optical counterpart and a radio counterpart that is also apparently modulated on the orbital period. 1FGL J1018.6-5856 is thus a gamma-ray binary, and its detection suggests the presence of other fainter binaries in the Galaxy.
View details for DOI 10.1126/science.1213974
View details for PubMedID 22246769
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Measurement of Separate Cosmic-Ray Electron and Positron Spectra with the Fermi Large Area Telescope
PHYSICAL REVIEW LETTERS
2012; 108 (1)
Abstract
We measured separate cosmic-ray electron and positron spectra with the Fermi Large Area Telescope. Because the instrument does not have an onboard magnet, we distinguish the two species by exploiting Earth's shadow, which is offset in opposite directions for opposite charges due to Earth's magnetic field. We estimate and subtract the cosmic-ray proton background using two different methods that produce consistent results. We report the electron-only spectrum, the positron-only spectrum, and the positron fraction between 20 and 200 GeV. We confirm that the fraction rises with energy in the 20-100 GeV range. The three new spectral points between 100 and 200 GeV are consistent with a fraction that is continuing to rise with energy.
View details for DOI 10.1103/PhysRevLett.108.011103
View details for Web of Science ID 000298928500005
View details for PubMedID 22304252
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FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE SUPERNOVA REMNANT G8.7-0.1
ASTROPHYSICAL JOURNAL
2012; 744 (1)
View details for DOI 10.1088/0004-637X/744/1/80
View details for Web of Science ID 000298408300080
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In-flight measurement of the absolute energy scale of the Fermi Large Area Telescope
ASTROPARTICLE PHYSICS
2012; 35 (6): 346-353
View details for DOI 10.1016/j.astropartphys.2011.10.007
View details for Web of Science ID 000300760800007
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THE SECOND CATALOG OF ACTIVE GALACTIC NUCLEI DETECTED BY THE FERMI LARGE AREA TELESCOPE
ASTROPHYSICAL JOURNAL
2011; 743 (2)
View details for DOI 10.1088/0004-637X/743/2/171
View details for Web of Science ID 000298178400073
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Constraining Dark Matter Models from a Combined Analysis of Milky Way Satellites with the Fermi Large Area Telescope
PHYSICAL REVIEW LETTERS
2011; 107 (24)
Abstract
Satellite galaxies of the Milky Way are among the most promising targets for dark matter searches in gamma rays. We present a search for dark matter consisting of weakly interacting massive particles, applying a joint likelihood analysis to 10 satellite galaxies with 24 months of data of the Fermi Large Area Telescope. No dark matter signal is detected. Including the uncertainty in the dark matter distribution, robust upper limits are placed on dark matter annihilation cross sections. The 95% confidence level upper limits range from about 10(-26) cm3 s(-1) at 5 GeV to about 5×10(-23) cm3 s(-1) at 1 TeV, depending on the dark matter annihilation final state. For the first time, using gamma rays, we are able to rule out models with the most generic cross section (∼3×10(-26) cm3 s(-1) for a purely s-wave cross section), without assuming additional boost factors.
View details for DOI 10.1103/PhysRevLett.107.241302
View details for PubMedID 22242987
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Fermi Detection of a Luminous gamma-Ray Pulsar in a Globular Cluster
SCIENCE
2011; 334 (6059): 1107-1110
View details for DOI 10.1126/science.1207141
View details for Web of Science ID 000297313900043
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A Cocoon of Freshly Accelerated Cosmic Rays Detected by Fermi in the Cygnus Superbubble
SCIENCE
2011; 334 (6059): 1103-1107
Abstract
The origin of Galactic cosmic rays is a century-long puzzle. Indirect evidence points to their acceleration by supernova shockwaves, but we know little of their escape from the shock and their evolution through the turbulent medium surrounding massive stars. Gamma rays can probe their spreading through the ambient gas and radiation fields. The Fermi Large Area Telescope (LAT) has observed the star-forming region of Cygnus X. The 1- to 100-gigaelectronvolt images reveal a 50-parsec-wide cocoon of freshly accelerated cosmic rays that flood the cavities carved by the stellar winds and ionization fronts from young stellar clusters. It provides an example to study the youth of cosmic rays in a superbubble environment before they merge into the older Galactic population.
View details for DOI 10.1126/science.1210311
View details for PubMedID 22116880
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gamma-RAY AND PARSEC-SCALE JET PROPERTIES OF A COMPLETE SAMPLE OF BLAZARS FROM THE MOJAVE PROGRAM
ASTROPHYSICAL JOURNAL
2011; 742 (1)
View details for DOI 10.1088/0004-637X/742/1/27
View details for Web of Science ID 000296783400027
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THE RADIO/GAMMA-RAY CONNECTION IN ACTIVE GALACTIC NUCLEI IN THE ERA OF THE FERMI LARGE AREA TELESCOPE
ASTROPHYSICAL JOURNAL
2011; 741 (1)
View details for DOI 10.1088/0004-637X/741/1/30
View details for Web of Science ID 000296769000030
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Simultaneous multi-wavelength campaign on PKS 2005-489 in a high state
ASTRONOMY & ASTROPHYSICS
2011; 533
View details for DOI 10.1051/0004-6361/201016170
View details for Web of Science ID 000295168100110
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Constraints on dark matter models from a Fermi LAT search for high-energy cosmic-ray electrons from the Sun
PHYSICAL REVIEW D
2011; 84 (3)
View details for DOI 10.1103/PhysRevD.84.032007
View details for Web of Science ID 000293844100001
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FERMI LARGE AREA TELESCOPE OBSERVATIONS OF MARKARIAN 421: THE MISSING PIECE OF ITS SPECTRAL ENERGY DISTRIBUTION
ASTROPHYSICAL JOURNAL
2011; 736 (2)
View details for DOI 10.1088/0004-637X/736/2/131
View details for Web of Science ID 000292977400056
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DISCOVERY OF HIGH-ENERGY GAMMA-RAY EMISSION FROM THE BINARY SYSTEM PSR B1259-63/LS 2883 AROUND PERIASTRON WITH FERMI
ASTROPHYSICAL JOURNAL LETTERS
2011; 736 (1)
View details for DOI 10.1088/2041-8205/736/1/L11
View details for Web of Science ID 000293138300011
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FERMI LARGE AREA TELESCOPE OBSERVATIONS OF TWO GAMMA-RAY EMISSION COMPONENTS FROM THE QUIESCENT SUN
ASTROPHYSICAL JOURNAL
2011; 734 (2)
View details for DOI 10.1088/0004-637X/734/2/116
View details for Web of Science ID 000291386500044
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DETECTION OF HIGH-ENERGY GAMMA-RAY EMISSION DURING THE X-RAY FLARING ACTIVITY IN GRB 100728A
ASTROPHYSICAL JOURNAL LETTERS
2011; 734 (2)
View details for DOI 10.1088/2041-8205/734/2/L27
View details for Web of Science ID 000293135700002
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OBSERVATIONS OF THE YOUNG SUPERNOVA REMNANT RX J1713.7-3946 WITH THE FERMI LARGE AREA TELESCOPE
ASTROPHYSICAL JOURNAL
2011; 734 (1)
View details for DOI 10.1088/0004-637X/734/1/28
View details for Web of Science ID 000291026900028
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FERMI GAMMA-RAY SPACE TELESCOPE OBSERVATIONS OF THE GAMMA-RAY OUTBURST FROM 3C454.3 IN NOVEMBER 2010
ASTROPHYSICAL JOURNAL LETTERS
2011; 733 (2)
View details for DOI 10.1088/2041-8205/733/2/L26
View details for Web of Science ID 000293135000010
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MULTI-WAVELENGTH OBSERVATIONS OF THE FLARING GAMMA-RAY BLAZAR 3C 66A IN 2008 OCTOBER (vol 726, pg 43, 2011)
ASTROPHYSICAL JOURNAL
2011; 731 (1)
View details for DOI 10.1088/0004-637X/731/1/77
View details for Web of Science ID 000289772800077
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THE FIRST FERMI MULTIFREQUENCY CAMPAIGN ON BL LACERTAE: CHARACTERIZING THE LOW-ACTIVITY STATE OF THE EPONYMOUS BLAZAR
ASTROPHYSICAL JOURNAL
2011; 730 (2)
View details for DOI 10.1088/0004-637X/730/2/101
View details for Web of Science ID 000288441900041
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DETECTION OF A SPECTRAL BREAK IN THE EXTRA HARD COMPONENT OF GRB 090926A
ASTROPHYSICAL JOURNAL
2011; 729 (2)
View details for DOI 10.1088/0004-637X/729/2/114
View details for Web of Science ID 000288608700037
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THE FIRST FERMI LARGE AREA TELESCOPE CATALOG OF GAMMA-RAY PULSARS (vol 187, pg 460, 2010)
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
2011; 193 (1)
View details for DOI 10.1088/0067-0049/193/1/22
View details for Web of Science ID 000289059000022
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RADIO AND gamma-RAY CONSTRAINTS ON THE EMISSION GEOMETRY AND BIRTHPLACE OF PSR J2043+2740
ASTROPHYSICAL JOURNAL
2011; 728 (2)
View details for DOI 10.1088/0004-637X/728/2/77
View details for Web of Science ID 000286973600004
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Gamma-Ray Flares from the Crab Nebula
SCIENCE
2011; 331 (6018): 739-742
Abstract
A young and energetic pulsar powers the well-known Crab Nebula. Here, we describe two separate gamma-ray (photon energy greater than 100 mega-electron volts) flares from this source detected by the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. The first flare occurred in February 2009 and lasted approximately 16 days. The second flare was detected in September 2010 and lasted approximately 4 days. During these outbursts, the gamma-ray flux from the nebula increased by factors of four and six, respectively. The brevity of the flares implies that the gamma rays were emitted via synchrotron radiation from peta-electron-volt (10(15) electron volts) electrons in a region smaller than 1.4 × 10(-2) parsecs. These are the highest-energy particles that can be associated with a discrete astronomical source, and they pose challenges to particle acceleration theory.
View details for DOI 10.1126/science.1199705
View details for Web of Science ID 000287205700062
View details for PubMedID 21212321
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INSIGHTS INTO THE HIGH-ENERGY gamma-RAY EMISSION OF MARKARIAN 501 FROM EXTENSIVE MULTIFREQUENCY OBSERVATIONS IN THE FERMI ERA
ASTROPHYSICAL JOURNAL
2011; 727 (2)
View details for DOI 10.1088/0004-637X/727/2/129
View details for Web of Science ID 000286662000068
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CONSTRAINTS ON THE COSMIC-RAY DENSITY GRADIENT BEYOND THE SOLAR CIRCLE FROM FERMI gamma-RAY OBSERVATIONS OF THE THIRD GALACTIC QUADRANT
ASTROPHYSICAL JOURNAL
2011; 726 (2)
View details for DOI 10.1088/0004-637X/726/2/81
View details for Web of Science ID 000285623600025
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MULTI-WAVELENGTH OBSERVATIONS OF THE FLARING GAMMA-RAY BLAZAR 3C 66A IN 2008 OCTOBER
ASTROPHYSICAL JOURNAL
2011; 726 (1)
View details for DOI 10.1088/0004-637X/726/1/43
View details for Web of Science ID 000285411300043
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FERMI-LAT SEARCH FOR PULSAR WIND NEBULAE AROUND GAMMA-RAY PULSARS
ASTROPHYSICAL JOURNAL
2011; 726 (1)
View details for DOI 10.1088/0004-637X/726/1/35
View details for Web of Science ID 000285411300035
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SEARCH FOR GAMMA-RAY EMISSION FROM MAGNETARS WITH THE FERMI LARGE AREA TELESCOPE
ASTROPHYSICAL JOURNAL LETTERS
2010; 725 (1): L73-L78
View details for DOI 10.1088/2041-8205/725/1/L73
View details for Web of Science ID 000284575400016
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A population of gamma-ray emitting globular clusters seen with the Fermi Large Area Telescope
ASTRONOMY & ASTROPHYSICS
2010; 524
View details for DOI 10.1051/0004-6361/201014458
View details for Web of Science ID 000284625300024
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Fermi LAT observations of cosmic-ray electrons from 7 GeV to 1 TeV
PHYSICAL REVIEW D
2010; 82 (9)
View details for DOI 10.1103/PhysRevD.82.092004
View details for Web of Science ID 000284402000002
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Searches for cosmic-ray electron anisotropies with the Fermi Large Area Telescope
PHYSICAL REVIEW D
2010; 82 (9)
View details for DOI 10.1103/PhysRevD.82.092003
View details for Web of Science ID 000284402000001
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FERMI LARGE AREA TELESCOPE CONSTRAINTS ON THE GAMMA-RAY OPACITY OF THE UNIVERSE
ASTROPHYSICAL JOURNAL
2010; 723 (2): 1082-1096
View details for DOI 10.1088/0004-637X/723/2/1082
View details for Web of Science ID 000284093700011
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Fermi Large Area Telescope observations of Local Group galaxies: detection of M31 and search for M33
ASTRONOMY & ASTROPHYSICS
2010; 523
View details for DOI 10.1051/0004-6361/201015759
View details for Web of Science ID 000285346600003
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FERMI LARGE AREA TELESCOPE OBSERVATION OF A GAMMA-RAY SOURCE AT THE POSITION OF ETA CARINAE
ASTROPHYSICAL JOURNAL
2010; 723 (1): 649-657
View details for DOI 10.1088/0004-637X/723/1/649
View details for Web of Science ID 000284090100057
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Detection of the Small Magellanic Cloud in gamma-rays with Fermi/LAT
ASTRONOMY & ASTROPHYSICS
2010; 523
View details for DOI 10.1051/0004-6361/201014855
View details for Web of Science ID 000285346600050
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FERMI-LAT STUDY OF GAMMA-RAY EMISSION IN THE DIRECTION OF SUPERNOVA REMNANT W49B
ASTROPHYSICAL JOURNAL
2010; 722 (2): 1303-1311
View details for DOI 10.1088/0004-637X/722/2/1303
View details for Web of Science ID 000284075400026
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GAMMA-RAY LIGHT CURVES AND VARIABILITY OF BRIGHT FERMI-DETECTED BLAZARS
ASTROPHYSICAL JOURNAL
2010; 722 (1): 520-542
View details for DOI 10.1088/0004-637X/722/1/520
View details for Web of Science ID 000282908900043
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FERMI GAMMA-RAY SPACE TELESCOPE OBSERVATIONS OF GAMMA-RAY OUTBURSTS FROM 3C 454.3 IN 2009 DECEMBER AND 2010 APRIL
ASTROPHYSICAL JOURNAL
2010; 721 (2): 1383-1396
View details for DOI 10.1088/0004-637X/721/2/1383
View details for Web of Science ID 000282193600036
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FERMI LARGE AREA TELESCOPE AND MULTI-WAVELENGTH OBSERVATIONS OF THE FLARING ACTIVITY OF PKS 1510-089 BETWEEN 2008 SEPTEMBER AND 2009 JUNE
ASTROPHYSICAL JOURNAL
2010; 721 (2): 1425-1447
View details for DOI 10.1088/0004-637X/721/2/1425
View details for Web of Science ID 000282193600041
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FERMI-LAT OBSERVATIONS OF THE GEMINGA PULSAR
ASTROPHYSICAL JOURNAL
2010; 720 (1): 272-283
View details for DOI 10.1088/0004-637X/720/1/272
View details for Web of Science ID 000281596000025
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FERMI LARGE AREA TELESCOPE OBSERVATIONS OF GAMMA-RAY PULSARS PSR J1057-5226, J1709-4429, AND J1952+3252
ASTROPHYSICAL JOURNAL
2010; 720 (1): 26-40
View details for DOI 10.1088/0004-637X/720/1/26
View details for Web of Science ID 000281596000004
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THE FERMI-LAT HIGH-LATITUDE SURVEY: SOURCE COUNT DISTRIBUTIONS AND THE ORIGIN OF THE EXTRAGALACTIC DIFFUSE BACKGROUND
ASTROPHYSICAL JOURNAL
2010; 720 (1): 435-453
View details for DOI 10.1088/0004-637X/720/1/435
View details for Web of Science ID 000281596000037
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FERMI LARGE AREA TELESCOPE OBSERVATIONS OF MISALIGNED ACTIVE GALACTIC NUCLEI
ASTROPHYSICAL JOURNAL
2010; 720 (1): 912-922
View details for DOI 10.1088/0004-637X/720/1/912
View details for Web of Science ID 000281596000077
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FERMI LARGE AREA TELESCOPE VIEW OF THE CORE OF THE RADIO GALAXY CENTAURUS A
ASTROPHYSICAL JOURNAL
2010; 719 (2): 1433-1444
View details for DOI 10.1088/0004-637X/719/2/1433
View details for Web of Science ID 000280658000033
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Gamma-Ray Emission Concurrent with the Nova in the Symbiotic Binary V407 Cygni
SCIENCE
2010; 329 (5993): 817-821
Abstract
Novae are thermonuclear explosions on a white dwarf surface fueled by mass accreted from a companion star. Current physical models posit that shocked expanding gas from the nova shell can produce x-ray emission, but emission at higher energies has not been widely expected. Here, we report the Fermi Large Area Telescope detection of variable gamma-ray emission (0.1 to 10 billion electron volts) from the recently detected optical nova of the symbiotic star V407 Cygni. We propose that the material of the nova shell interacts with the dense ambient medium of the red giant primary and that particles can be accelerated effectively to produce pi(0) decay gamma-rays from proton-proton interactions. Emission involving inverse Compton scattering of the red giant radiation is also considered and is not ruled out.
View details for DOI 10.1126/science.1192537
View details for Web of Science ID 000280809900044
View details for PubMedID 20705855
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FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE SUPERNOVA REMNANT W28 (G6.4-0.1)
ASTROPHYSICAL JOURNAL
2010; 718 (1): 348-356
View details for DOI 10.1088/0004-637X/718/1/348
View details for Web of Science ID 000280340800029
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FERMI OBSERVATIONS OF HIGH-ENERGY GAMMA-RAY EMISSION FROM GRB 090217A
ASTROPHYSICAL JOURNAL LETTERS
2010; 717 (2): L127-L132
View details for DOI 10.1088/2041-8205/717/2/L127
View details for Web of Science ID 000279430700011
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GeV GAMMA-RAY FLUX UPPER LIMITS FROM CLUSTERS OF GALAXIES
ASTROPHYSICAL JOURNAL LETTERS
2010; 717 (1): L71-L78
View details for DOI 10.1088/2041-8205/717/1/L71
View details for Web of Science ID 000279430600015
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FERMI OBSERVATIONS OF GRB 090510: A SHORT-HARD GAMMA-RAY BURST WITH AN ADDITIONAL, HARD POWER-LAW COMPONENT FROM 10 keV TO GeV ENERGIES
ASTROPHYSICAL JOURNAL
2010; 716 (2): 1178-1190
View details for DOI 10.1088/0004-637X/716/2/1178
View details for Web of Science ID 000278459000022
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SUZAKU OBSERVATIONS OF LUMINOUS QUASARS: REVEALING THE NATURE OF HIGH-ENERGY BLAZAR EMISSION IN LOW-LEVEL ACTIVITY STATES
ASTROPHYSICAL JOURNAL
2010; 716 (1): 835-849
View details for DOI 10.1088/0004-637X/716/1/835
View details for Web of Science ID 000277960000064
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THE SPECTRAL ENERGY DISTRIBUTION OF FERMI BRIGHT BLAZARS
ASTROPHYSICAL JOURNAL
2010; 716 (1): 30-70
View details for DOI 10.1088/0004-637X/716/1/30
View details for Web of Science ID 000277960000002
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FERMI LARGE AREA TELESCOPE FIRST SOURCE CATALOG
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
2010; 188 (2): 405-436
View details for DOI 10.1088/0067-0049/188/2/405
View details for Web of Science ID 000278969400004
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THE FIRST CATALOG OF ACTIVE GALACTIC NUCLEI DETECTED BY THE FERMI LARGE AREA TELESCOPE
ASTROPHYSICAL JOURNAL
2010; 715 (1): 429-457
View details for DOI 10.1088/0004-637X/715/1/429
View details for Web of Science ID 000277216100036
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THE DISCOVERY OF gamma-RAY EMISSION FROM THE BLAZAR RGB J0710+591
ASTROPHYSICAL JOURNAL LETTERS
2010; 715 (1): L49-L55
View details for DOI 10.1088/2041-8205/715/1/L49
View details for Web of Science ID 000277233200011
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Fermi Gamma-Ray Imaging of a Radio Galaxy
SCIENCE
2010; 328 (5979): 725-729
Abstract
The Fermi Gamma-ray Space Telescope has detected the gamma-ray glow emanating from the giant radio lobes of the radio galaxy Centaurus A. The resolved gamma-ray image shows the lobes clearly separated from the central active source. In contrast to all other active galaxies detected so far in high-energy gamma-rays, the lobe flux constitutes a considerable portion (greater than one-half) of the total source emission. The gamma-ray emission from the lobes is interpreted as inverse Compton-scattered relic radiation from the cosmic microwave background, with additional contribution at higher energies from the infrared-to-optical extragalactic background light. These measurements provide gamma-ray constraints on the magnetic field and particle energy content in radio galaxy lobes, as well as a promising method to probe the cosmic relic photon fields.
View details for DOI 10.1126/science.1184656
View details for Web of Science ID 000277357100032
View details for PubMedID 20360067
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FERMI-LARGE AREA TELESCOPE OBSERVATIONS OF THE EXCEPTIONAL GAMMA-RAY OUTBURSTS OF 3C 273 IN 2009 SEPTEMBER
ASTROPHYSICAL JOURNAL LETTERS
2010; 714 (1): L73-L78
View details for DOI 10.1088/2041-8205/714/1/L73
View details for Web of Science ID 000276971300015
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DETECTION OF THE ENERGETIC PULSAR PSR B1509-58 AND ITS PULSAR WIND NEBULA IN MSH 15-52 USING THE FERMI-LARGE AREA TELESCOPE
ASTROPHYSICAL JOURNAL
2010; 714 (1): 927-936
View details for DOI 10.1088/0004-637X/714/1/927
View details for Web of Science ID 000276701000076
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Constraints on dark matter annihilation in clusters of galaxies with the Fermi large area telescope
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
2010
View details for DOI 10.1088/1475-7516/2010/05/025
View details for Web of Science ID 000279490800015
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FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE VELA-X PULSAR WIND NEBULA
ASTROPHYSICAL JOURNAL
2010; 713 (1): 146-153
View details for DOI 10.1088/0004-637X/713/1/146
View details for Web of Science ID 000275918500013
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THE VELA PULSAR: RESULTS FROM THE FIRST YEAR OF FERMI LAT OBSERVATIONS
ASTROPHYSICAL JOURNAL
2010; 713 (1): 154-165
View details for DOI 10.1088/0004-637X/713/1/154
View details for Web of Science ID 000275918500014
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FERMI LARGE AREA TELESCOPE OBSERVATIONS OF PSR J1836+5925
ASTROPHYSICAL JOURNAL
2010; 712 (2): 1209-1218
View details for DOI 10.1088/0004-637X/712/2/1209
View details for Web of Science ID 000275594600037
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DISCOVERY OF PULSED gamma-RAYS FROM PSR J0034-0534 WITH THE FERMI LARGE AREA TELESCOPE: A CASE FOR CO-LOCATED RADIO AND gamma-RAY EMISSION REGIONS
ASTROPHYSICAL JOURNAL
2010; 712 (2): 957-963
View details for DOI 10.1088/0004-637X/712/2/957
View details for Web of Science ID 000275594600016
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Constraints on cosmological dark matter annihilation from the Fermi-LAT isotropic diffuse gamma-ray measurement
JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
2010
View details for DOI 10.1088/1475-7516/2010/04/014
View details for Web of Science ID 000277684600019
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THE FIRST FERMI LARGE AREA TELESCOPE CATALOG OF GAMMA-RAY PULSARS
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
2010; 187 (2): 460-494
View details for DOI 10.1088/0067-0049/187/2/460
View details for Web of Science ID 000276841500007
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OBSERVATION OF SUPERNOVA REMNANT IC 443 WITH THE FERMI LARGE AREA TELESCOPE
ASTROPHYSICAL JOURNAL
2010; 712 (1): 459-468
View details for DOI 10.1088/0004-637X/712/1/459
View details for Web of Science ID 000275222900041
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FERMI DETECTION DELAYED GeV EMISSION FROM THE SHORT GAMMA-RAY BURST 081024B
ASTROPHYSICAL JOURNAL
2010; 712 (1): 558-564
View details for DOI 10.1088/0004-637X/712/1/558
View details for Web of Science ID 000275222900049
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OBSERVATIONS OF MILKY WAY DWARF SPHEROIDAL GALAXIES WITH THE FERMI-LARGE AREA TELESCOPE DETECTOR AND CONSTRAINTS ON DARK MATTER MODELS
ASTROPHYSICAL JOURNAL
2010; 712 (1): 147-158
View details for DOI 10.1088/0004-637X/712/1/147
View details for Web of Science ID 000275222900013
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Spectrum of the Isotropic Diffuse Gamma-Ray Emission Derived from First-Year Fermi Large Area Telescope Data
PHYSICAL REVIEW LETTERS
2010; 104 (10)
Abstract
We report on the first Fermi Large Area Telescope (LAT) measurements of the so-called "extragalactic" diffuse gamma-ray emission (EGB). This component of the diffuse gamma-ray emission is generally considered to have an isotropic or nearly isotropic distribution on the sky with diverse contributions discussed in the literature. The derivation of the EGB is based on detailed modeling of the bright foreground diffuse Galactic gamma-ray emission, the detected LAT sources, and the solar gamma-ray emission. We find the spectrum of the EGB is consistent with a power law with a differential spectral index gamma = 2.41 +/- 0.05 and intensity I(>100 MeV) = (1.03 +/- 0.17) x 10(-5) cm(-2) s(-1) sr(-1), where the error is systematics dominated. Our EGB spectrum is featureless, less intense, and softer than that derived from EGRET data.
View details for DOI 10.1103/PhysRevLett.104.101101
View details for Web of Science ID 000275543500007
View details for PubMedID 20366411
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Fermi Large Area Telescope Search for Photon Lines from 30 to 200 GeV and Dark Matter Implications
PHYSICAL REVIEW LETTERS
2010; 104 (9)
Abstract
Dark matter (DM) particle annihilation or decay can produce monochromatic gamma rays readily distinguishable from astrophysical sources. gamma-ray line limits from 30 to 200 GeV obtained from 11 months of Fermi Large Area Space Telescope data from 20-300 GeV are presented using a selection based on requirements for a gamma-ray line analysis, and integrated over most of the sky. We obtain gamma-ray line flux upper limits in the range 0.6-4.5x10{-9} cm{-2} s{-1}, and give corresponding DM annihilation cross-section and decay lifetime limits. Theoretical implications are briefly discussed.
View details for DOI 10.1103/PhysRevLett.104.091302
View details for Web of Science ID 000275252500009
View details for PubMedID 20366979
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Observations of the Large Magellanic Cloud with Fermi
ASTRONOMY & ASTROPHYSICS
2010; 512
View details for DOI 10.1051/0004-6361/200913474
View details for Web of Science ID 000276245500019
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PSR J1907+0602: A RADIO-FAINT GAMMA-RAY PULSAR POWERING A BRIGHT TeV PULSAR WIND NEBULA
ASTROPHYSICAL JOURNAL
2010; 711 (1): 64-74
View details for DOI 10.1088/0004-637X/711/1/64
View details for Web of Science ID 000274417500006
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Gamma-Ray Emission from the Shell of Supernova Remnant W44 Revealed by the Fermi LAT
SCIENCE
2010; 327 (5969): 1103-1106
Abstract
Recent observations of supernova remnants (SNRs) hint that they accelerate cosmic rays to energies close to ~10(15) electron volts. However, the nature of the particles that produce the emission remains ambiguous. We report observations of SNR W44 with the Fermi Large Area Telescope at energies between 2 x 10(8) electron volts and 3 x10(11) electron volts. The detection of a source with a morphology corresponding to the SNR shell implies that the emission is produced by particles accelerated there. The gamma-ray spectrum is well modeled with emission from protons and nuclei. Its steepening above approximately 10(9) electron volts provides a probe with which to study how particle acceleration responds to environmental effects such as shock propagation in dense clouds and how accelerated particles are released into interstellar space.
View details for DOI 10.1126/science.1182787
View details for Web of Science ID 000274901100028
View details for PubMedID 20056857
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SPECTRAL PROPERTIES OF BRIGHT FERMI-DETECTED BLAZARS IN THE GAMMA-RAY BAND
ASTROPHYSICAL JOURNAL
2010; 710 (2): 1271-1285
View details for DOI 10.1088/0004-637X/710/2/1271
View details for Web of Science ID 000274233300027
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A change in the optical polarization associated with a gamma-ray flare in the blazar 3C 279
NATURE
2010; 463 (7283): 919-923
Abstract
It is widely accepted that strong and variable radiation detected over all accessible energy bands in a number of active galaxies arises from a relativistic, Doppler-boosted jet pointing close to our line of sight. The size of the emitting zone and the location of this region relative to the central supermassive black hole are, however, poorly known, with estimates ranging from light-hours to a light-year or more. Here we report the coincidence of a gamma (gamma)-ray flare with a dramatic change of optical polarization angle. This provides evidence for co-spatiality of optical and gamma-ray emission regions and indicates a highly ordered jet magnetic field. The results also require a non-axisymmetric structure of the emission zone, implying a curved trajectory for the emitting material within the jet, with the dissipation region located at a considerable distance from the black hole, at about 10(5) gravitational radii.
View details for DOI 10.1038/nature08841
View details for Web of Science ID 000274582700039
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FERMI-LAT DISCOVERY OF GeV GAMMA-RAY EMISSION FROM THE YOUNG SUPERNOVA REMNANT CASSIOPEIA A
ASTROPHYSICAL JOURNAL LETTERS
2010; 710 (1): L92-L97
View details for DOI 10.1088/2041-8205/710/1/L92
View details for Web of Science ID 000274438700020
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PKS 1502+106: A NEW AND DISTANT GAMMA-RAY BLAZAR IN OUTBURST DISCOVERED BY THE FERMI LARGE AREA TELESCOPE
ASTROPHYSICAL JOURNAL
2010; 710 (1): 810-827
View details for DOI 10.1088/0004-637X/710/1/810
View details for Web of Science ID 000273850800063
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FERMI OBSERVATIONS OF CASSIOPEIA AND CEPHEUS: DIFFUSE GAMMA-RAY EMISSION IN THE OUTER GALAXY
ASTROPHYSICAL JOURNAL
2010; 710 (1): 133-149
View details for DOI 10.1088/0004-637X/710/1/133
View details for Web of Science ID 000273850800015
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DETECTION OF GAMMA-RAY EMISSION FROM THE STARBURST GALAXIES M82 AND NGC 253 WITH THE LARGE AREA TELESCOPE ON FERMI
ASTROPHYSICAL JOURNAL LETTERS
2010; 709 (2): L152-L157
View details for DOI 10.1088/2041-8205/709/2/L152
View details for Web of Science ID 000274209300013
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SWIFT AND FERMI OBSERVATIONS OF THE EARLY AFTERGLOW OF THE SHORT GAMMA-RAY BURST 090510
ASTROPHYSICAL JOURNAL LETTERS
2010; 709 (2): L146-L151
View details for DOI 10.1088/2041-8205/709/2/L146
View details for Web of Science ID 000274209300012
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FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE CRAB PULSAR AND NEBULA
ASTROPHYSICAL JOURNAL
2010; 708 (2): 1254-1267
View details for DOI 10.1088/0004-637X/708/2/1254
View details for Web of Science ID 000273021000024
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FERMI OBSERVATIONS OF THE VERY HARD GAMMA-RAY BLAZAR PG 1553+113
ASTROPHYSICAL JOURNAL
2010; 708 (2): 1310-1320
View details for DOI 10.1088/0004-637X/708/2/1310
View details for Web of Science ID 000273021000028
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GAMMA-RAY AND RADIO PROPERTIES OF SIX PULSARS DETECTED BY THE FERMI LARGE AREA TELESCOPE
ASTROPHYSICAL JOURNAL
2010; 708 (2): 1426-1441
View details for DOI 10.1088/0004-637X/708/2/1426
View details for Web of Science ID 000273021000038
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DISCOVERY OF VERY HIGH ENERGY GAMMA RAYS FROM PKS 1424+240 AND MULTIWAVELENGTH CONSTRAINTS ON ITS REDSHIFT
ASTROPHYSICAL JOURNAL LETTERS
2010; 708 (2): L100-L106
View details for DOI 10.1088/2041-8205/708/2/L100
View details for Web of Science ID 000273308000007
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FERMI OBSERVATIONS OF TeV-SELECTED ACTIVE GALACTIC NUCLEI
ASTROPHYSICAL JOURNAL
2009; 707 (2): 1310-1333
View details for DOI 10.1088/0004-637X/707/2/1310
View details for Web of Science ID 000272465400039
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RADIO-LOUD NARROW-LINE SEYFERT 1 AS A NEW CLASS OF GAMMA-RAY ACTIVE GALACTIC NUCLEI
ASTROPHYSICAL JOURNAL LETTERS
2009; 707 (2): L142-L147
View details for DOI 10.1088/0004-637X/707/2/L142
View details for Web of Science ID 000272465800008
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Fermi Large Area Telescope Measurements of the Diffuse Gamma-Ray Emission at Intermediate Galactic Latitudes
PHYSICAL REVIEW LETTERS
2009; 103 (25)
Abstract
The diffuse galactic gamma-ray emission is produced by cosmic rays (CRs) interacting with the interstellar gas and radiation field. Measurements by the Energetic Gamma-Ray Experiment Telescope (EGRET) instrument on the Compton Gamma-Ray Observatory indicated excess gamma-ray emission greater, > or approximately equal to 1 GeV relative to diffuse galactic gamma-ray emission models consistent with directly measured CR spectra (the so-called "EGRET GeV excess"). The Large Area Telescope (LAT) instrument on the Fermi Gamma-Ray Space Telescope has measured the diffuse gamma-ray emission with improved sensitivity and resolution compared to EGRET. We report on LAT measurements for energies 100 MeV to 10 GeV and galactic latitudes 10 degrees < or = |b| < or = 20 degrees. The LAT spectrum for this region of the sky is well reproduced by a diffuse galactic gamma-ray emission model that is consistent with local CR spectra and inconsistent with the EGRET GeV excess.
View details for DOI 10.1103/PhysRevLett.103.251101
View details for Web of Science ID 000272958300005
View details for PubMedID 20366246
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Modulated High-Energy Gamma-Ray Emission from the Microquasar Cygnus X-3
SCIENCE
2009; 326 (5959): 1512-1516
Abstract
Microquasars are accreting black holes or neutron stars in binary systems with associated relativistic jets. Despite their frequent outburst activity, they have never been unambiguously detected emitting high-energy gamma rays. The Fermi Large Area Telescope (LAT) has detected a variable high-energy source coinciding with the position of the x-ray binary and microquasar Cygnus X-3. Its identification with Cygnus X-3 is secured by the detection of its orbital period in gamma rays, as well as the correlation of the LAT flux with radio emission from the relativistic jets of Cygnus X-3. The gamma-ray emission probably originates from within the binary system, opening new areas in which to study the formation of relativistic jets.
View details for DOI 10.1126/science.1182174
View details for Web of Science ID 000272623600051
View details for PubMedID 19965378
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MULTIWAVELENGTH MONITORING OF THE ENIGMATIC NARROW-LINE SEYFERT 1 PMN J0948+0022 IN 2009 MARCH-JULY
ASTROPHYSICAL JOURNAL
2009; 707 (1): 727-737
View details for DOI 10.1088/0004-637X/707/1/727
View details for Web of Science ID 000272162900059
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FERMI OBSERVATIONS OF HIGH-ENERGY GAMMA-RAY EMISSION FROM GRB 080825C
ASTROPHYSICAL JOURNAL
2009; 707 (1): 580-592
View details for DOI 10.1088/0004-637X/707/1/580
View details for Web of Science ID 000272162900045
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FERMI LARGE AREA TELESCOPE GAMMA-RAY DETECTION OF THE RADIO GALAXY M87
ASTROPHYSICAL JOURNAL
2009; 707 (1): 55-60
View details for DOI 10.1088/0004-637X/707/1/55
View details for Web of Science ID 000272162900004
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Fermi large area telescope observations of the cosmic-ray induced gamma-ray emission of the Earth's atmosphere
PHYSICAL REVIEW D
2009; 80 (12)
View details for DOI 10.1103/PhysRevD.80.122004
View details for Web of Science ID 000273233300010
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FERMI LARGE AREA TELESCOPE DETECTION OF PULSED gamma-RAYS FROM THE VELA-LIKE PULSARS PSR J1048-5832 AND PSR J2229+6114
ASTROPHYSICAL JOURNAL
2009; 706 (2): 1331-1340
View details for DOI 10.1088/0004-637X/706/2/1331
View details for Web of Science ID 000271872900032
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FERMI/LAT OBSERVATIONS OF LS 5039
ASTROPHYSICAL JOURNAL LETTERS
2009; 706 (1): L56-L61
View details for DOI 10.1088/0004-637X/706/1/L56
View details for Web of Science ID 000271533200012
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FERMI OBSERVATIONS OF GRB 090902B: A DISTINCT SPECTRAL COMPONENT IN THE PROMPT AND DELAYED EMISSION
ASTROPHYSICAL JOURNAL LETTERS
2009; 706 (1): L138-L144
View details for DOI 10.1088/0004-637X/706/1/L138
View details for Web of Science ID 000271533200029
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FERMI LAT DISCOVERY OF EXTENDED GAMMA-RAY EMISSION IN THE DIRECTION OF SUPERNOVA REMNANT W51C
ASTROPHYSICAL JOURNAL LETTERS
2009; 706 (1): L1-L6
View details for DOI 10.1088/0004-637X/706/1/L1
View details for Web of Science ID 000271533200001
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A limit on the variation of the speed of light arising from quantum gravity effects
NATURE
2009; 462 (7271): 331-334
Abstract
A cornerstone of Einstein's special relativity is Lorentz invariance-the postulate that all observers measure exactly the same speed of light in vacuum, independent of photon-energy. While special relativity assumes that there is no fundamental length-scale associated with such invariance, there is a fundamental scale (the Planck scale, l(Planck) approximately 1.62 x 10(-33) cm or E(Planck) = M(Planck)c(2) approximately 1.22 x 10(19) GeV), at which quantum effects are expected to strongly affect the nature of space-time. There is great interest in the (not yet validated) idea that Lorentz invariance might break near the Planck scale. A key test of such violation of Lorentz invariance is a possible variation of photon speed with energy. Even a tiny variation in photon speed, when accumulated over cosmological light-travel times, may be revealed by observing sharp features in gamma-ray burst (GRB) light-curves. Here we report the detection of emission up to approximately 31 GeV from the distant and short GRB 090510. We find no evidence for the violation of Lorentz invariance, and place a lower limit of 1.2E(Planck) on the scale of a linear energy dependence (or an inverse wavelength dependence), subject to reasonable assumptions about the emission (equivalently we have an upper limit of l(Planck)/1.2 on the length scale of the effect). Our results disfavour quantum-gravity theories in which the quantum nature of space-time on a very small scale linearly alters the speed of light.
View details for DOI 10.1038/nature08574
View details for Web of Science ID 000271899300039
View details for PubMedID 19865083
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FERMI LAT OBSERVATION OF DIFFUSE GAMMA RAYS PRODUCED THROUGH INTERACTIONS BETWEEN LOCAL INTERSTELLAR MATTER AND HIGH-ENERGY COSMIC RAYS
ASTROPHYSICAL JOURNAL
2009; 703 (2): 1249-1256
View details for DOI 10.1088/0004-637X/703/2/1249
View details for Web of Science ID 000269929500007
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The on-orbit calibration of the Fermi Large Area Telescope
ASTROPARTICLE PHYSICS
2009; 32 (3-4): 193-219
View details for DOI 10.1016/j.astropartphys.2009.08.002
View details for Web of Science ID 000272276400005
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FERMI LAT OBSERVATIONS OF LS I+61 degrees 303: FIRST DETECTION OF AN ORBITAL MODULATION IN GeV GAMMA RAYS
ASTROPHYSICAL JOURNAL LETTERS
2009; 701 (2): L123-L128
View details for DOI 10.1088/0004-637X/701/2/L123
View details for Web of Science ID 000268867900014
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Detection of 16 Gamma-Ray Pulsars Through Blind Frequency Searches Using the Fermi LAT
SCIENCE
2009; 325 (5942): 840-844
Abstract
Pulsars are rapidly rotating, highly magnetized neutron stars emitting radiation across the electromagnetic spectrum. Although there are more than 1800 known radio pulsars, until recently only seven were observed to pulse in gamma rays, and these were all discovered at other wavelengths. The Fermi Large Area Telescope (LAT) makes it possible to pinpoint neutron stars through their gamma-ray pulsations. We report the detection of 16 gamma-ray pulsars in blind frequency searches using the LAT. Most of these pulsars are coincident with previously unidentified gamma-ray sources, and many are associated with supernova remnants. Direct detection of gamma-ray pulsars enables studies of emission mechanisms, population statistics, and the energetics of pulsar wind nebulae and supernova remnants.
View details for DOI 10.1126/science.1175558
View details for Web of Science ID 000269242400037
View details for PubMedID 19574346
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Detection of High-Energy Gamma-Ray Emission from the Globular Cluster 47 Tucanae with Fermi
SCIENCE
2009; 325 (5942): 845-848
Abstract
We report the detection of gamma-ray emissions above 200 megaelectron volts at a significance level of 17sigma from the globular cluster 47 Tucanae, using data obtained with the Large Area Telescope onboard the Fermi Gamma-ray Space Telescope. Globular clusters are expected to emit gamma rays because of the large populations of millisecond pulsars that they contain. The spectral shape of 47 Tucanae is consistent with gamma-ray emission from a population of millisecond pulsars. The observed gamma-ray luminosity implies an upper limit of 60 millisecond pulsars present in 47 Tucanae.
View details for DOI 10.1126/science.1177023
View details for Web of Science ID 000269242400038
View details for PubMedID 19679807
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A Population of Gamma-Ray Millisecond Pulsars Seen with the Fermi Large Area Telescope
SCIENCE
2009; 325 (5942): 848-852
Abstract
Pulsars are born with subsecond spin periods and slow by electromagnetic braking for several tens of millions of years, when detectable radiation ceases. A second life can occur for neutron stars in binary systems. They can acquire mass and angular momentum from their companions, to be spun up to millisecond periods and begin radiating again. We searched Fermi Large Area Telescope data for pulsations from all known millisecond pulsars (MSPs) outside of globular clusters, using rotation parameters from radio telescopes. Strong gamma-ray pulsations were detected for eight MSPs. The gamma-ray pulse profiles and spectral properties resemble those of young gamma-ray pulsars. The basic emission mechanism seems to be the same for MSPs and young pulsars, with the emission originating in regions far from the neutron star surface.
View details for DOI 10.1126/science.1176113
View details for Web of Science ID 000269242400039
View details for PubMedID 19574349
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PULSED GAMMA-RAYS FROM PSR J2021+3651 WITH THE FERMI LARGE AREA TELESCOPE
ASTROPHYSICAL JOURNAL
2009; 700 (2): 1059-1066
View details for DOI 10.1088/0004-637X/700/2/1059
View details for Web of Science ID 000268098100020
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BRIGHT ACTIVE GALACTIC NUCLEI SOURCE LIST FROM THE FIRST THREE MONTHS OF THE FERMI LARGE AREA TELESCOPE ALL-SKY SURVEY
ASTROPHYSICAL JOURNAL
2009; 700 (1): 597-622
View details for DOI 10.1088/0004-637X/700/1/597
View details for Web of Science ID 000267768900049
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PULSED GAMMA RAYS FROM THE MILLISECOND PULSAR J0030+0451 WITH THE FERMI LARGE AREA TELESCOPE
ASTROPHYSICAL JOURNAL
2009; 699 (2): 1171-1177
View details for DOI 10.1088/0004-637X/699/2/1171
View details for Web of Science ID 000267401500026
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DISCOVERY OF PULSATIONS FROM THE PULSAR J0205+6449 IN SNR 3C 58 WITH THE FERMI GAMMA-RAY SPACE TELESCOPE
ASTROPHYSICAL JOURNAL LETTERS
2009; 699 (2): L102-L107
View details for DOI 10.1088/0004-637X/699/2/L102
View details for Web of Science ID 000267372800011
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FERMI/LARGE AREA TELESCOPE DISCOVERY OF GAMMA-RAY EMISSION FROM A RELATIVISTIC JET IN THE NARROW-LINE QUASAR PMN J0948+0022
ASTROPHYSICAL JOURNAL
2009; 699 (2): 976-984
View details for DOI 10.1088/0004-637X/699/2/976
View details for Web of Science ID 000267401500008
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FERMI/LARGE AREA TELESCOPE BRIGHT GAMMA-RAY SOURCE LIST
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
2009; 183 (1): 46-66
View details for DOI 10.1088/0067-0049/183/1/46
View details for Web of Science ID 000267656000004
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FERMI DISCOVERY OF GAMMA-RAY EMISSION FROM NGC 1275
ASTROPHYSICAL JOURNAL
2009; 699 (1): 31-39
View details for DOI 10.1088/0004-637X/699/1/31
View details for Web of Science ID 000267056300004
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EARLY FERMI GAMMA-RAY SPACE TELESCOPE OBSERVATIONS OF THE QUASAR 3C 454.3
ASTROPHYSICAL JOURNAL
2009; 699 (1): 817-823
View details for DOI 10.1088/0004-637X/699/1/817
View details for Web of Science ID 000267056300061
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THE LARGE AREA TELESCOPE ON THE FERMI GAMMA-RAY SPACE TELESCOPE MISSION
ASTROPHYSICAL JOURNAL
2009; 697 (2): 1071-1102
View details for DOI 10.1088/0004-637X/697/2/1071
View details for Web of Science ID 000266159500012
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FERMI/LARGE AREA TELESCOPE DISCOVERY OF GAMMA-RAY EMISSION FROM THE FLAT-SPECTRUM RADIO QUASAR PKS 1454-354
ASTROPHYSICAL JOURNAL
2009; 697 (1): 934-941
View details for DOI 10.1088/0004-637X/697/1/934
View details for Web of Science ID 000265764000080
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FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE VELA PULSAR
ASTROPHYSICAL JOURNAL
2009; 696 (2): 1084-1093
View details for DOI 10.1088/0004-637X/696/2/1084
View details for Web of Science ID 000265762700003
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SIMULTANEOUS OBSERVATIONS OF PKS 2155-304 WITH HESS, FERMI, RXTE, AND ATOM: SPECTRAL ENERGY DISTRIBUTIONS AND VARIABILITY IN A LOW STATE
ASTROPHYSICAL JOURNAL LETTERS
2009; 696 (2): L150-L155
View details for DOI 10.1088/0004-637X/696/2/L150
View details for Web of Science ID 000265531500010
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Measurement of the Cosmic Ray e(+)+e(-) Spectrum from 20 GeV to 1 TeV with the Fermi Large Area Telescope
PHYSICAL REVIEW LETTERS
2009; 102 (18)
Abstract
Designed as a high-sensitivity gamma-ray observatory, the Fermi Large Area Telescope is also an electron detector with a large acceptance exceeding 2 m;{2} sr at 300 GeV. Building on the gamma-ray analysis, we have developed an efficient electron detection strategy which provides sufficient background rejection for measurement of the steeply falling electron spectrum up to 1 TeV. Our high precision data show that the electron spectrum falls with energy as E-3.0 and does not exhibit prominent spectral features. Interpretations in terms of a conventional diffusive model as well as a potential local extra component are briefly discussed.
View details for DOI 10.1103/PhysRevLett.102.181101
View details for Web of Science ID 000265948600011
View details for PubMedID 19518855
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DISCOVERY OF PULSED gamma-RAYS FROM THE YOUNG RADIO PULSAR PSR J1028-5819 WITH THE FERMI LARGE AREA TELESCOPE
ASTROPHYSICAL JOURNAL LETTERS
2009; 695 (1): L72-L77
View details for DOI 10.1088/0004-637X/695/1/L72
View details for Web of Science ID 000264539700016
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Fermi Observations of High-Energy Gamma-Ray Emission from GRB 080916C
SCIENCE
2009; 323 (5922): 1688-1693
Abstract
Gamma-ray bursts (GRBs) are highly energetic explosions signaling the death of massive stars in distant galaxies. The Gamma-ray Burst Monitor and Large Area Telescope onboard the Fermi Observatory together record GRBs over a broad energy range spanning about 7 decades of gammaray energy. In September 2008, Fermi observed the exceptionally luminous GRB 080916C, with the largest apparent energy release yet measured. The high-energy gamma rays are observed to start later and persist longer than the lower energy photons. A simple spectral form fits the entire GRB spectrum, providing strong constraints on emission models. The known distance of the burst enables placing lower limits on the bulk Lorentz factor of the outflow and on the quantum gravity mass.
View details for DOI 10.1126/science.1169101
View details for Web of Science ID 000264559800029
View details for PubMedID 19228997
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The Fermi Gamma-Ray Space Telescope Discovers the Pulsar in the Young Galactic Supernova Remnant CTA 1
SCIENCE
2008; 322 (5905): 1218-1221
Abstract
Energetic young pulsars and expanding blast waves [supernova remnants (SNRs)] are the most visible remains after massive stars, ending their lives, explode in core-collapse supernovae. The Fermi Gamma-Ray Space Telescope has unveiled a radio quiet pulsar located near the center of the compact synchrotron nebula inside the supernova remnant CTA 1. The pulsar, discovered through its gamma-ray pulsations, has a period of 316.86 milliseconds and a period derivative of 3.614 x 10(-13) seconds per second. Its characteristic age of 10(4) years is comparable to that estimated for the SNR. We speculate that most unidentified Galactic gamma-ray sources associated with star-forming regions and SNRs are such young pulsars.
View details for DOI 10.1126/science.1165572
View details for Web of Science ID 000261033400033
View details for PubMedID 18927355
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Environmental tests of the flight GLAST LAT tracker towers
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT
2008; 584 (2-3): 358-373
View details for DOI 10.1016/j.nima.2007.10.035
View details for Web of Science ID 000253081800013
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Construction, test and calibration of the GLAST silicon tracker
6th International Conference on Radiation Effects on Semiconductor Materials, Detectors, and Devices
ELSEVIER SCIENCE BV. 2007: 9–13
View details for DOI 10.1016/j.nima.2007.08.224
View details for Web of Science ID 000251861100003
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Design and initial tests of the Tracker-converter of the Gamma-ray Large Area Space Telescope
ASTROPARTICLE PHYSICS
2007; 28 (4-5): 422-434
View details for DOI 10.1016/j.astropartphys.2007.08.010
View details for Web of Science ID 000251839600005
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Measurements of charmless hadronic two-body B meson decays and the ratio B(B -> DK)/B(B -> D pi) (vol 68, art no 052002, 2003)
PHYSICAL REVIEW D
2007; 75 (11)
View details for DOI 10.1103/PhysRevD.75.119907
View details for Web of Science ID 000247625300069
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Measurements of charmless hadronic two-body B meson decays and the ratio B(B -> DK)/(B -> D pi)
PHYSICAL REVIEW D
2003; 68 (5)
View details for DOI 10.1103/PhysRevD.68.052002
View details for Web of Science ID 000185720000005
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Study of the charmless inclusive B ->eta ' X decay
PHYSICAL REVIEW D
2003; 68 (1)
View details for DOI 10.1103/PhysRevD.68.011101
View details for Web of Science ID 000184583700001
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Search for B ->(p)over-bare-(nu)over-bar(e) X decay using a partial reconstruction method
PHYSICAL REVIEW D
2003; 68 (1)
View details for DOI 10.1103/PhysRevD.68.012004
View details for Web of Science ID 000184583700009
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Measurements of the branching fractions and helicity amplitudes in B -> D-*rho decays
PHYSICAL REVIEW D
2003; 67 (11)
View details for DOI 10.1103/PhysRevD.67.112002
View details for Web of Science ID 000183915300004
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Branching fractions of tau leptons to three charged hadrons
PHYSICAL REVIEW LETTERS
2003; 90 (18)
Abstract
From electron-positron collision data collected with the CLEO detector operating at Cornell Electron Storage Ring near sqrt[s]=10.6 GeV, improved measurements of the branching fractions for tau decays into three explicitly identified hadrons and a neutrino are presented as B(tau(-)-->pi(-)pi(+)pi(-)nu(tau))=(9.13+/-0.05+/-0.46)%, B(tau(-)-->K-pi(+)pi(-)nu(tau))=(3.84+/-0.14+/-0.38) x 10(-3), B(tau(-)-->K-K+pi(-)nu(tau))=(1.55+/-0.06+/-0.09) x 10(-3), and B(tau(-)-->K-K+K-nu(tau))<3.7 x 10(-5) at 90% C.L., where the uncertainties are statistical and systematic, respectively.
View details for DOI 10.1103/PhysRevLett.90.181802
View details for Web of Science ID 000182823900007
View details for PubMedID 12785998
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Measurement of lepton momentum moments in the decay (B)over-bar -> Xl(nu)over-bar and determination of the heavy quark expansion parameters and vertical bar V-cb vertical bar
PHYSICAL REVIEW D
2003; 67 (7)
View details for DOI 10.1103/PhysRevD.67.072001
View details for Web of Science ID 000182718300009
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First search for the flavor changing neutral current decay D-0 -> gamma gamma
PHYSICAL REVIEW LETTERS
2003; 90 (10)
Abstract
Using 13.8 fb(-1) of data collected at or just below the Upsilon(4S) with the CLEO detector, we report the result of a search for the flavor changing neutral current process D0-->gammagamma. We observe no significant signal for this decay mode and determine 90% confidence level upper limits on the branching fractions B(D0-->gammagamma)/B(D0-->pi(0)pi(0))<0.033 and B(D0-->gammagamma)<2.9 x 10(-5).
View details for DOI 10.1103/PhysRevLett.90.101801
View details for Web of Science ID 000181597500008
View details for PubMedID 12688989
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Inclusive eta(') production from the Upsilon(1S)
PHYSICAL REVIEW D
2003; 67 (5)
View details for DOI 10.1103/PhysRevD.67.052003
View details for Web of Science ID 000182019700005
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Dalitz analysis of D-0 -> K-S(0)pi(+)pi(-) (vol 90, art no 251802, 2002)
PHYSICAL REVIEW LETTERS
2003; 90 (5)
View details for DOI 10.1103/PhysRevLett.90.059901
View details for Web of Science ID 000180918300073
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Determination of the (B)over-bar -> D(*)l(nu)over-bar decay width and vertical bar V-cb vertical bar
PHYSICAL REVIEW D
2003; 67 (3)
View details for DOI 10.1103/PhysRevD.67.032001
View details for Web of Science ID 000181431400003
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First observation of the exclusive decays Lambda(+)(c)->Lambda pi(+)pi(+)pi(-)pi(0) and Lambda(+)(c)->Lambda omega pi(+)
PHYSICAL REVIEW D
2003; 67 (1)
View details for DOI 10.1103/PhysRevD.67.012001
View details for Web of Science ID 000180918100003
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Measurements of inclusive B ->psi production
PHYSICAL REVIEW LETTERS
2002; 89 (28)
Abstract
Using the combined CLEO II and CLEO II.V data sets of 9.1 fb(-1) at the Upsilon(4S), we measure properties of psi mesons produced directly from decays of the B meson, where "B" denotes an admixture of B+, B-, B0, and B;(0), and "psi" denotes either J/psi(1S) or psi(2S). We report first measurements of psi polarization in B-->psi(direct)X: alpha(psi(1S))=-0.30(+0.07)(-0.06)+/-0.04 and alpha(psi(2S))=-0.45(+0.22)(-0.19)+/-0.04. We also report improved measurements of the momentum distributions of psi produced directly from B decays, correcting for measurement smearing. Finally, we report measurements of the inclusive branching fraction for B-->psiX and B-->chi(c1)X.
View details for DOI 10.1103/PhysRevLett.89.282001
View details for Web of Science ID 000180317900010
View details for PubMedID 12513135
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Observation of B -> K-S(0)pi(+)pi(-) and evidence for B -> K-*+/-pi(-/+)
PHYSICAL REVIEW LETTERS
2002; 89 (25)
Abstract
We report on a search for charmless hadronic B decays to the three-body final states K(0)(S)h(+)pi(-), K(+)h(-)pi(0), K(0)(S)h(+)pi(0) (h(+/-) denotes a charged pion or kaon), and their charge conjugates, using 13.5 fb(-1) of integrated luminosity produced near sqrt[s]=10.6 GeV, and collected with the CLEO detector. We observe the decay B-->K0pi(+)pi(-) with a branching fraction (50(+10)(-9)(stat.)+/-7(syst.))x10(-6) and the decay B-->K(*+)(892)pi(-) with a branching fraction (16(+6)(-5)(stat.)+/-2(syst.))x10(-6).
View details for DOI 10.1103/PhysRevLett.89.251801
View details for Web of Science ID 000179678900007
View details for PubMedID 12484873
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Dalitz analysis of D-0 -> K-S(0)pi(+)pi(-)
PHYSICAL REVIEW LETTERS
2002; 89 (25)
Abstract
In e(+)e(-) collisions using the CLEO detector, we have studied the decay of the D0 to the final state K(0)(S)pi(+)pi(-) with the initial flavor of the D0 tagged by the decay D(*+)-->D0pi(+). We use the Dalitz technique to measure the resonant substructure in this final state and clearly observe ten different contributions by fitting for their amplitudes and relative phases. We observe a K(*)(892)(+)pi(-) component which arises from doubly Cabibbo suppressed decays or D0-D0; mixing.
View details for DOI 10.1103/PhysRevLett.89.251802
View details for Web of Science ID 000179678900008
View details for PubMedID 12484874
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Measurement of B(D+->(K)over-bar(*0)l(+)nu(l))
PHYSICAL REVIEW LETTERS
2002; 89 (22)
Abstract
Using 13.53 fb(-1) of CLEO data, we have measured the ratios of the branching fractions R(+)(e),R(+)(mu) and the combined branching fraction ratio R(+)(l), defined by R(+)(l)=[B(D+-->K(*0)l(+)nu(l))]/[B(D+-->K-pi(+)pi(+))]. We find R(+)(e)=0.74+/-0.04+/-0.05, R(+)(mu)=0.72+/-0.10+/-0.05, and R(+)(l)=0.74+/-0.04+/-0.05, where the first and second errors are statistical and systematic, respectively. The known branching fraction B(D+-->K-pi(+)pi(+)) leads to B(D+-->K(*0)e(+)nu(e))=(6.7+/-0.4+/-0.5+/-0.4)%, B(D+-->K(*0)mu(+)nu(mu))=(6.5+/-0.9+/-0.5+/-0.4)%, and B(D+-->K(*0)l(+)nu(l))=(6.7+/-0.4+/-0.5+/-0.4)%, where the third error is due to the uncertainty in B(D+-->K-pi(+)pi(+)).
View details for DOI 10.1103/PhysRevLett.89.222001
View details for Web of Science ID 000179205100010
View details for PubMedID 12485061
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Measurement of exclusive Beta decays to final states containing a charmed baryon
PHYSICAL REVIEW D
2002; 66 (9)
View details for DOI 10.1103/PhysRevD.66.091101
View details for Web of Science ID 000179679400001
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Observation of the decay Omega(0)(c)->Omega(-)e(+)nu(e)
PHYSICAL REVIEW LETTERS
2002; 89 (17)
Abstract
Using the CLEO detector at the Cornell Electron Storage Ring we have observed the Omega(0)(c) (css ground state) in the decay Omega(0)(c)-->Omega(-)e(+)nu(e). We find a signal of 11.4+/-3.8(stat) events. The probability that we have observed a background fluctuation is 7.6x10(-5). We measure B(Omega(0)(c)-->Omega(-)e(+)nu(e)).sigma(e(+)e(-)-->Omega(0)(c)X)=(42.2+/-14.1(stat)+/-5.7(syst)) fb and R=[Gamma(Omega(0)(c)-->Omega(-)pi(+))]/[Gamma(Omega(0)(c)-->Omega(-)enu(e))]=00.41+/-0.19(stat)+/-0.04(syst). This is the first statistically significant observation of an individual decay mode of the Omega(0)(c) in e(+)e(-) annihilation and the first example of a baryon decaying via beta emission, where no quarks from the first generation participate in the reaction.
View details for DOI 10.1103/PhysRevLett.89.171803
View details for Web of Science ID 000178483500012
View details for PubMedID 12398660
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Search for neutrinoless tau decays involving the K-S(0) meson
PHYSICAL REVIEW D
2002; 66 (7)
View details for DOI 10.1103/PhysRevD.66.071101
View details for Web of Science ID 000179068200001
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Antisearch for the glueball candidate f(J)(2220) in two-photon interactions
PHYSICAL REVIEW D
2002; 66 (7)
View details for DOI 10.1103/PhysRevD.66.077101
View details for Web of Science ID 000179068200072
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Correlated inclusive Lambda(Lambda)over-bar production in e(+)e(-) annihilations at root s similar to 10.5 GeV
PHYSICAL REVIEW D
2002; 66 (5)
View details for DOI 10.1103/PhysRevD.66.052002
View details for Web of Science ID 000178460700005
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Measurement of the ratio of branching fractions of the Upsilon(4S) to charged and neutral B mesons
PHYSICAL REVIEW D
2002; 66 (5)
View details for DOI 10.1103/PhysRevD.66.052003
View details for Web of Science ID 000178460700006
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Improved measurement of vertical bar V-cb vertical bar using (B)over-bar -> D(*)l(nu)over-bar decays
PHYSICAL REVIEW LETTERS
2002; 89 (8)
View details for DOI 10.1103/PhysRevLett.89.081803
View details for Web of Science ID 000177338700011
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Improved measurement of /V(cb)/ using B-->D*l nu decays.
Physical review letters
2002; 89 (8): 081803-?
Abstract
We determine the weak coupling /V(cb)/ between the b and c quarks using a sample of 3 x 10(6) BB; events in the CLEO detector at the Cornell Electron Storage Ring. We determine the yield of reconstructed B-->D*l nu; decays as a function of w, the boost of the D* in the B rest frame, and from this we obtain the differential decay rate d Gamma/dw. By extrapolating d Gamma/dw to w=1, the kinematic end point at which the D* is at rest relative to the B, we extract the product /V(cb)/F(1), where F(1) is the form factor at w=1. Combined with theoretical results for F(1) we determine /V(cb)/=0.0469+/-0.0014(stat)+/-0.0020(syst)+/-0.0018(theor).
View details for PubMedID 12190458
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Measurement of B(B--> D-0 pi(-)) and B((B)over-bar(0)-> D+pi(-)) and isospin analysis of (B)over-bar -> D pi decays
PHYSICAL REVIEW D
2002; 66 (3)
View details for DOI 10.1103/PhysRevD.66.031101
View details for Web of Science ID 000177873600001
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Improved measurement of vertical bar V-ub vertical bar with inclusive semileptonic B decays
PHYSICAL REVIEW LETTERS
2002; 88 (23)
View details for DOI 10.1103/PhysRevLett.88.231803
View details for Web of Science ID 000175860500015
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Improved measurement of Vub with inclusive semileptonic B decays.
Physical review letters
2002; 88 (23): 231803-?
Abstract
We report a new measurement of the Cabibbo-Kobayashi-Maskawa parameter Vub made with a sample of 9.7 x 10(6) BB- events collected with the CLEO II detector. Using heavy quark theory, we combine the observed yield of leptons from semileptonic B decay in the end-point momentum interval 2.2-2.6 GeV/c with recent CLEO II data on B-->X(s)gamma to find Vub = (4.08+/-0.34+/-0.44+/-0.16+/-0.24)x10(-3), where the first two uncertainties are experimental and the last two are from theory.
View details for PubMedID 12059353
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Search for lepton-flavor-violating decays of B mesons
PHYSICAL REVIEW D
2002; 65 (11)
View details for DOI 10.1103/PhysRevD.65.111102
View details for Web of Science ID 000176770900002
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Lifetime differences, direct CP violation, and partial widths in D-0 meson decays to K+K- and pi(+)pi(-)
PHYSICAL REVIEW D
2002; 65 (9)
View details for DOI 10.1103/PhysRevD.65.092001
View details for Web of Science ID 000175914500011
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Measurement of the masses and widths of the Sigma(++)(c) and Sigma(0)(c) charmed baryons
PHYSICAL REVIEW D
2002; 65 (7)
View details for DOI 10.1103/PhysRevD.65.071101
View details for Web of Science ID 000174980100001
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Further experimental studies of two-body radiative Upsilon decays
PHYSICAL REVIEW D
2002; 65 (7)
View details for DOI 10.1103/PhysRevD.65.072002
View details for Web of Science ID 000174980100005
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Search for CP violation in tau -> K pi nu(tau) decays
PHYSICAL REVIEW LETTERS
2002; 88 (11)
Abstract
We search and find no evidence for CP violation in tau decays into the K(pi)nu(tau) final state. We provide limits on the imaginary part of the coupling constant Lambda describing a relative contribution of the CP violating processes with respect to the standard model to be -0.172
View details for DOI 10.1103/PhysRevLett.88.111803
View details for Web of Science ID 000174541700008
View details for PubMedID 11909396
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Observation of exclusive (B)over-bar -> (DK*-)-K-(*) decays
PHYSICAL REVIEW LETTERS
2002; 88 (10)
Abstract
We report the first observation of the exclusive decays B-->D((*))K(*-), using 9.66 x 10(6) BB pairs collected at the Upsilon(4S) with the CLEO detector. We measure the following branching fractions: B(B--->D(0)K(*-)) = (6.1+/-1.6+/-1.7)x10(-4), B(B(0)-->D(+)K(*-)) = (3.7+/-1.5+/-1.0)x10(-4), B(B(0)-->D(*+)K(*-)) = (3.8+/-1.3+/-0.8)x10(-4), and B(B--->D(*0)K(*-)) = (7.7+/-2.2+/-2.6)x10(-4). The B-->D(*)K(*-) branching ratios are the averages of those corresponding to the 00 and 11 helicity states. The errors shown are statistical and systematic, respectively.
View details for DOI 10.1103/PhysRevLett.88.101803
View details for Web of Science ID 000174342000014
View details for PubMedID 11909343
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Observation of (B)over-bar(0)-> D-0 pi(0) and (B)over-bar(0)-> D*(0)pi(0)
PHYSICAL REVIEW LETTERS
2002; 88 (6)
View details for DOI 10.1103/PhysRevLett.88.062001
View details for Web of Science ID 000173849300006
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Observation of B(0) --> D0pi(0) and B(0) -->D(*0)pi(0).
Physical review letters
2002; 88 (6): 062001-?
Abstract
We have studied the color-suppressed hadronic decays of neutral B mesons into the final states D*0pi(0). Using 9.67 x 10(6) BB pairs collected with the CLEO detector, we observe the decays B( 0) --> D0pi(0) and B( 0) -->D(*0)pi(0) with the branching fractions BB( 0) -->D0pi(0)) = (2.74(+0.36)(-0.32) +/- 0.55)x10(-4) and BB( 0) -->D(*0)pi(0)) = (2.20(+0.59)(-0.52) +/- 0.79)x10(-4). The first error is statistical and the second systematic. The statistical significance of the D0pi(0) signal is 12.1sigma ( 5.9sigma for D(*0)pi(0)). Utilizing the B( 0) -->D*0)pi(0) branching fractions we determine the strong phases delta(I,D(*)) between isospin 1/2 and 3/2 amplitudes in the Dpi and D*pi final states to be cosdelta(I,D) = 0.89 +/-0.08 and cosdelta(I,D*) = 0.89 +/- 0.08, respectively.
View details for PubMedID 11863797
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Publisher's note: Observation of (B)over-bar(0)-> D-0 pi(0) and (B)over-bar(0)-> D-*0 pi(0) (vol 88, art no 062001, 2002)
PHYSICAL REVIEW LETTERS
2002; 88 (6)
View details for DOI 10.1103/PhysRevLett.88.069902
View details for Web of Science ID 000173849300079
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First measurement of Gamma(D*+) and precision measurement of m(D)*+(-)m(D)(0)
PHYSICAL REVIEW D
2002; 65 (3)
View details for DOI 10.1103/PhysRevD.65.032003
View details for Web of Science ID 000173793300007
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Search for B-0 ->pi(0) pi(0) decay
PHYSICAL REVIEW D
2002; 65 (3)
View details for DOI 10.1103/PhysRevD.65.031103
View details for Web of Science ID 000173793300003
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Search for charmless B -> VV decays
PHYSICAL REVIEW LETTERS
2002; 88 (2)
Abstract
We have studied two-body charmless decays of the B meson into the final states rho(0)rho(0), K(*0)rho(0), K(*0)K(*0), K(*0)K(*0), K(*+)rho(0), K(*+)K(*0), and K(*+)K(*-) using only decay modes with charged daughter particles. Using 9.7x10(6) BB pairs collected with the CLEO detector, we place 90% confidence level upper limits on the branching fractions (1.4-14.1)x10(-5), depending on final state and polarization.
View details for DOI 10.1103/PhysRevLett.88.021802
View details for Web of Science ID 000173350600007
View details for PubMedID 11801004
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First observation of (B)over-bar(0)-> D*(0)pi(+)pi(+)pi(-)pi(-) decays
PHYSICAL REVIEW D
2002; 65 (1)
View details for DOI 10.1103/PhysRevD.65.012002
View details for Web of Science ID 000173125000002
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Search for the familon via B-+/-->pi X-+/-(0), B-+/-->(KX0)-X-+/-, and B-0 ->(KSX0)-X-0 decays
PHYSICAL REVIEW LETTERS
2001; 87 (27)
Abstract
We have searched for the two-body decay of the B meson to a light pseudoscalar meson h = pi(+/-),K+/-,K(0)(S) and a massless neutral feebly interacting particle X(0) such as the familon, the Nambu-Goldstone boson associated with a spontaneously broken global family symmetry. We find no significant signal by analyzing a data sample containing 9.7x10(6) BBbar mesons collected with the CLEO detector at the Cornell Electron Storage Ring, and set 90% C.L. upper limits italicB(B(+/-) --> h(+/-)X(0)) = 4.9x10(-5) and italicB(B(0) --> K(0)(S)X(0)) = 5.3x10(-5). These limits correspond to a lower bound of approximately 10(8) GeV on the family symmetry breaking scale with vector coupling involving the third generation of quarks.
View details for DOI 10.1103/PhysRevLett.87.271801
View details for Web of Science ID 000173040800013
View details for PubMedID 11800872
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First measurement of Gamma(D*(+))
PHYSICAL REVIEW LETTERS
2001; 87 (25)
Abstract
We present the first measurement of the D*(+) width using 9/fb of e(+)e(-) data collected near the Upsilon(4S) resonance by the CLEO II.V detector. Our method uses advanced tracking techniques and a reconstruction method that takes advantage of the small vertical size of the Cornell Electron-positron Storage Ring beam spot to measure the energy release distribution from the D*(+)-->D(0)pi(+) decay. We find gamma(D*(+)) = 96+/-4 (stat)+/-22 (syst) keV. We also measure the energy release in the decay and compute Delta m identical with m(D*(+))-m(D(0)) = 145.412+/-0.002 (stat)+/-0.012 (syst) MeV/c(2).
View details for DOI 10.1103/PhysRevLett.87.251801
View details for Web of Science ID 000172866200010
View details for PubMedID 11736560
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Hadronic mass moments in inclusive semileptonic B meson decays
PHYSICAL REVIEW LETTERS
2001; 87 (25)
Abstract
We have measured the first and second moments of the hadronic mass-squared distribution in B-->X(c)l nu, for P(lepton)>1.5 GeV/c. We find
= 0.251+/-0.066 GeV(2), <(M(2)(X)- )(2)> = 0.576+/-0.170 GeV(4), where M macro(D) is the spin-averaged D meson mass. From that first moment and the first moment of the photon energy spectrum in b-->s gamma, we find the heavy quark effective theory parameter lambda(1) (in the modified minimal subtraction renormalization scheme, to order 1/M(3)(B) and beta(0)alpha(2)(s)) to be -0.24+/-0.11 GeV(2). Using these first moments and the B semileptonic width, and assuming parton-hadron duality, we obtain absolute value of V(cb) = 0.0404+/-0.0013. View details for DOI 10.1103/PhysRevLett.87.251808
View details for Web of Science ID 000172866200017
View details for PubMedID 11736567
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Branching fraction and photon energy spectrum for b -> s gamma
PHYSICAL REVIEW LETTERS
2001; 87 (25)
Abstract
We have measured the branching fraction and photon energy spectrum for the radiative penguin process b-->s gamma. We find Beta(b-->s gamma) = (3.21+/-0.43+/-0.27(+0.18)(-0.10))x10(-4), where the errors are statistical, systematic, and from theory corrections. We obtain first and second moments of the photon energy spectrum above 2.0 GeV,
= 2.346+/-0.032+/-0.011 GeV, and - (2) = 0.0226+/-0.0066+/-0.0020 GeV(2), where the errors are statistical and systematic. From the first moment, we obtain (in the modified minimal subtraction renormalization scheme, to order 1/M(3)(B) and beta(0)alpha(2)(s)) the heavy quark effective theory parameter Lambda = 0.35+/-0.08+/-0.10 GeV. View details for DOI 10.1103/PhysRevLett.87.251807
View details for Web of Science ID 000172866200016
View details for PubMedID 11736566
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Evidence for the decay D-0 -> K+pi(-)pi(+)pi(-)
PHYSICAL REVIEW D
2001; 64 (11)
View details for DOI 10.1103/PhysRevD.64.111101
View details for Web of Science ID 000172450600001
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First observation of (B)over-bar -> D-(*)rho '(-), rho '(-)->omega pi(-)
PHYSICAL REVIEW D
2001; 64 (9)
View details for Web of Science ID 000171852100003
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Search for CP violation in tau ->pi pi(0)nu(tau) decay
PHYSICAL REVIEW D
2001; 64 (9)
View details for Web of Science ID 000171852100007
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Improved upper limits on the flavor-changing neutral current decays B -> Kl(+)l(-) and B -> K*(892)l(+)l(-)
PHYSICAL REVIEW LETTERS
2001; 87 (18)
View details for DOI 10.1103/PhysRevLett.87.181803
View details for Web of Science ID 000171909500008
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Search for the decay B+->(D*+KS0)
PHYSICAL REVIEW D
2001; 64 (7)
View details for Web of Science ID 000171280300081
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Search for the decay Y(1S) - gamma eta '
PHYSICAL REVIEW LETTERS
2001; 87 (14)
Abstract
We report on a search for the radiative decay Upsilon(1S)-->gammaeta(') in 61.3 pb(-1) of data taken with the CLEO II detector at the Cornell Electron Storage Ring. Three decay chains were investigated, all involving eta(')-->pi(+)pi(-)eta, followed by eta-->gammagamma, eta-->pi(0)pi(0)pi(0), or eta-->pi(+)pi(-)pi(0). We find no candidate events in any of the three cases and set a combined upper limit of 1.6x10(-5) at 90% C.L., significantly smaller than the previous limit. We compare our result to other radiative Upsilon decays, to radiative J/psi decays, and to theoretical predictions.
View details for DOI 10.1103/PhysRevLett.87.141801
View details for Web of Science ID 000171427500010
View details for PubMedID 11580641
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Rate measurement of D0 -> K+pi-pi 0 and constraints on D-0 D(0)over-bar mixing
PHYSICAL REVIEW LETTERS
2001; 87 (7)
Abstract
We present an observation and time-integrated rate measurement of the decay D(0)-->K(+)pi(-)pi(0) produced in 9 fb(-1) of e(+)e(-) collisions near the Upsilon(4S) resonance. The signal is inconsistent with an upward fluctuation of the background by 4.9 standard deviations. We measured the time-integrated rate of D(0)-->K(+)pi(-)pi(0) normalized to the rate of D(0)-->K(+)pi(-)pi(0) to be 0.0043(+0.0011)(-0.0010) (stat)+/-0.0007 (syst). This decay can be produced by doubly Cabibbo-suppressed decays or by the D(0) evolving into a D(0) through mixing, followed by a Cabibbo-favored decay to K(+)pi(-)pi(0). We also found the CP asymmetry A = (9(+25)(-22))% be consistent with zero.
View details for DOI 10.1103/PhysRevLett.87.071802
View details for Web of Science ID 000170478300007
View details for PubMedID 11497880
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Experimental investigation of the two-photon widths of the chi(c0) and the chi(c2) mesons
PHYSICAL REVIEW LETTERS
2001; 87 (6)
Abstract
Using 12.7 fb(-1) of data collected with the CLEO detector at CESR, we observed two-photon production of the cc states chi(c0) and chi(c2) in their decay to pi(+)pi(-)pi(+)pi(-). We measured gamma(gammagamma)(chi(c))xB(chi(c)-->pi(+)pi(-)pi(+)pi(-)) to be 75+/-13(stat)+/-8(syst) eV for the chi(c0) and 6.4+/-1.8(stat)+/-0.8(syst) eV for the chi(c2), implying gamma(gammagamma)(chi(c0)) = 3.76+/-0.65(stat)+/-0.41(syst)+/-1.69(br) keV and gamma(gammagamma)(chi(c2)) = 0.53+/-0.15(stat)+/-0.06(syst)+/-0.22(br) keV. Also, cancellation of dominant experimental and theoretical uncertainties permits a precise comparison of gamma(gammagamma)(chi(c0))/gamma(gammagamma)(chi(c2)), evaluated to be 7.4+/-2.4(stat)+/-0.5(syst)+/-0.9(br), with QCD-based predictions.
View details for DOI 10.1103/PhysRevLett.87.061801
View details for Web of Science ID 000170310200006
View details for PubMedID 11497821
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Bounds on the CP asymmetry in b -> s gamma decays
PHYSICAL REVIEW LETTERS
2001; 86 (25): 5661-5665
Abstract
We have measured the CP asymmetry A(CP) identical with[gamma(b-->sgamma)-gammab-->sgamma)]/[gamma(b-->sgamma)+gamma(b-->sgamma)] to be A(CP) = (-0.079+/-0.108+/-0.022) (1.0+/-0.030), implying that, at 90% confidence level, A(CP) lies between -0.27 and +0.10. These limits rule out some extreme non-standard-model predictions, but are consistent with most, as well as with the standard model.
View details for Web of Science ID 000169373000006
View details for PubMedID 11415327
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Measurement of the decay asymmetry parameters in Xi(0)(c)->Xi(-)pi(+)
PHYSICAL REVIEW D
2001; 63 (11)
View details for Web of Science ID 000169031600002
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Correlated Lambda(+)(c)(lambda)over-bar(c)(-) production in e(+)e(-) annihilations at root s similar to 10.5 GeV
PHYSICAL REVIEW D
2001; 63 (11)
View details for Web of Science ID 000169031600007
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Bounds on the CP asymmetry in like-sign dileptons from B-0(B)over-bar(0) meson decays
PHYSICAL REVIEW LETTERS
2001; 86 (22): 5000-5003
Abstract
We have measured the charge asymmetry in like-sign dilepton yields from B(0)B*(0) meson decays using the CLEO detector at the Cornell Electron Storage Ring. We find a(0)(ll) identical with[N(l(+)l(+))-N(l(-)l(-))]/[N(l(+)l(+))+N(l(-)l(-))] = +0.013+/-0.050+/-0.005. We combine this result with a previous, independent measurement and obtain Re(epsilon(B))/(1+ the absolute value of epsilon(B)(2)) = +0.0035+/-0.0103+/-0.0015 (uncertainties are statistical and systematic, respectively) for the CP impurity parameter, epsilon(B).
View details for Web of Science ID 000169013600005
View details for PubMedID 11384405
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Observation of new states decaying into Lambda(+)(c)pi(-)pi(+)
PHYSICAL REVIEW LETTERS
2001; 86 (20): 4479-4482
Abstract
Using 13.7 fb(-1) of data recorded by the CLEO detector at the Cornell Electron Storage Ring, we investigate the spectrum of charmed baryons which decay into Lambda+(c)pi(-)pi(+) and are more massive than the Lambda+(c)(2625) baryon. We find evidence for two new states: one is broad and has an invariant mass roughly 480 MeV above that of the Lambda+(c) baryon; the other is narrow with an invariant mass of 596+/-1+/-2 MeV above the Lambda+(c) mass.
View details for Web of Science ID 000168623500014
View details for PubMedID 11384263
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Study of tau decays to six pions and a neutrino
PHYSICAL REVIEW LETTERS
2001; 86 (20): 4467-4471
Abstract
The tau decays to six-pion final states have been studied with the CLEO detector at the Cornell Electron Storage Ring. The measured branching fractions are B(tau(-)-->2pi(-)pi(+)3pi(0)nu(tau)) = (2.2+/-0.3+/-0.4)x10(-4) and B(tau(-)-->3pi(-)2pi(+)pi(0)nu(tau)) = (1.7+/-0.2+/-0.2)x10(-4). A search for substructure in these decays shows that they are saturated by intermediate states with eta or omega mesons. We present the first observation of the decay tau(-)-->2pi(-)pi(+)omega(nu)tau and the branching fraction is measured to be (1.2+/-0.2+/-0.1)x10(-4). The measured branching fractions are in good agreement with the isospin expectations but somewhat below the conserved-vector-current predictions.
View details for Web of Science ID 000168623500012
View details for PubMedID 11384261
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Evidence of new states decaying into Xi*(c)pi
PHYSICAL REVIEW LETTERS
2001; 86 (19): 4243-4246
Abstract
Using 13.7 fb(-1) of data recorded by the CLEO detector at Cornell Electron Storage Ring, we report evidence of two new charmed baryons: one decaying into Xi(0')(c)pi(+) with the subsequent decay Xi(0')(c)-->Xi(0)(c)gamma, and its isospin partner decaying into Xi(+')(c)pi(-) followed by Xi(+')(c)-->Xi(+)(c)gamma. We measure the following mass differences for the two states: M(Xi(0)(c)gammapi(+))-M(Xi(0)(c)) = 318.2+/-1.3+/-2.9 MeV and M(Xi(+)(c)gammapi(-))-M(Xi(+)(c)) = 324.0+/-1.3+/-3.0 MeV. We interpret these new states as the J(P) = 1 / 2(-) Xi(c1) particles, the charmed-strange analogs of the Lambda(+)(c1)(2593).
View details for Web of Science ID 000168591000013
View details for PubMedID 11328145
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Dalitz analysis of the decay D-0 -> K- pi(+) pi(0)
PHYSICAL REVIEW D
2001; 63 (9)
View details for Web of Science ID 000168450800004
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Observation af the Omega(0)(c) charmed baryon at CLEO
PHYSICAL REVIEW LETTERS
2001; 86 (17): 3730-3734
Abstract
The CLEO experiment at the CESR collider has used 13.7 fb(-1) of data to search for the production of the Omega(0)(c) (css ground state) in e(+)e(-) collisions at square root of (s) approximately 10.6 GeV. The modes used to study the Omega(0)(c) are Omega(-)pi(+), Omega(-)pi(+)pi(0), Xi-K-pi(+)pi(+), Xi0K-pi(+), and Omega(-)pi(+)pi(+)pi(-). We observe a signal of 40.4+/-9.0(stat) events at a mass of 2694.6+/-2.6(stat)+/-1.9(syst) MeV/c(2), for all modes combined.
View details for Web of Science ID 000168338300009
View details for PubMedID 11329310
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Observation of B ->phi K and B ->phi K
PHYSICAL REVIEW LETTERS
2001; 86 (17): 3718-3721
Abstract
We have studied two-body charmless hadronic decays of B mesons into the final states straight phiK and phiK(*). Using 9.7 million B&Bmacr; pairs collected with the CLEO II detector, we observe the decays B- --> phiK- and B0--> phiK(*0) with the following branching fractions: B(B--->phiK-) = (5.5(+2.1)(-1.8)+/-0.6)x10(-6) and B(B0--> phiK(*0)) = (11.5(+4.5+1.8)(-3.7-1.7))x10(-6). We also see evidence for the decays B0-->phiK0 and B---> phiK(*-). However, since the statistical significance is not overwhelming for these modes, we determine upper limits of <12.3x10(-6) and <22.5x10(-6) ( 90% confidence level), respectively.
View details for Web of Science ID 000168338300006
View details for PubMedID 11329307
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Search for B --> tau(nu) and B --> K(nu)nu.
Physical review letters
2001; 86 (14): 2950-2954
Abstract
We report results of a search for B-->tau(nu) in a sample of 9.7 x 10(6) charged B meson decays. We exclusively reconstruct the companion B decay to suppress background. We set an upper limit on the branching fraction B(B-->tau(nu))<8.4 x 10(-4) at 90% confidence level. We also establish B(B+/--->K+/-nu(nu))<2.4 x 10(-4) at 90% confidence level.
View details for PubMedID 11290080
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Search for B ->tau nu and B -> K nu(nu)over-bar
PHYSICAL REVIEW LETTERS
2001; 86 (14): 2950-2954
Abstract
We report results of a search for B-->tau(nu) in a sample of 9.7 x 10(6) charged B meson decays. We exclusively reconstruct the companion B decay to suppress background. We set an upper limit on the branching fraction B(B-->tau(nu))<8.4 x 10(-4) at 90% confidence level. We also establish B(B+/--->K+/-nu(nu))<2.4 x 10(-4) at 90% confidence level.
View details for Web of Science ID 000167866300010
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Search for CP violation in D-0 -> K-S(0)pi(0), D-0 ->pi(0)pi(0) and D-0 ->(KSKS0)-K-0 decays
PHYSICAL REVIEW D
2001; 63 (7)
View details for Web of Science ID 000167792200001
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First observation of the decays B-0 -> D*- p(p)over-tilde pi(+) and B-0 -> D*- p(n)over-bar
PHYSICAL REVIEW LETTERS
2001; 86 (13): 2732-2736
Abstract
We report the first observation of exclusive decays of the type B-->D(*)N_NX, where N is a nucleon. Using a sample of 9.7x10(6)B_B pairs collected with the CLEO detector operating at the Cornell Electron Storage Ring, we measure the branching fractions B(B0-->D(*-)p_p pi(+)) = (6.5(+1.3)(-1.2)+/-1.0)x10(-4) and B(B0-->D(*-)p_n) = (14.5(+3.4)(-3.0)+/-2.7)x10(-4). Antineutrons are identified by their annihilation in the CsI electromagnetic calorimeter.
View details for Web of Science ID 000167693000009
View details for PubMedID 11290026
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Measurement of the relative branching fraction of gamma r(4S) to charged and neutral B-meson pairs
PHYSICAL REVIEW LETTERS
2001; 86 (13): 2737-2741
Abstract
We analyze 9.7x10(6) B_B pairs recorded with the CLEO detector to determine the production ratio of charged to neutral B-meson pairs produced at the Upsilon(4S) resonance. We measure the rates for B0-->J/psiK((*)0) and B+-->J/psiK((*)+) decays and use the world-average B-meson lifetime ratio to extract the relative widths f(+-) / f(00) = gamma(Upsilon(4S)-->B+B-) / gamma(Upsilon(4S)-->B0 B-0)) = 1.04+/-0.07(stat)+/-0.04(syst). With the assumption that f(+-)+f(00) = 1, we obtain f(00) = 0.49+/-0.02(stat)+/-0.01(syst) and f(+-) = 0.51+/-0.02(stat)+/-0.01(syst). This production ratio and its uncertainty apply to all exclusive B-meson branching fractions measured at the Upsilon(4S) resonance.
View details for Web of Science ID 000167693000010
View details for PubMedID 11290027
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Measurement of the Lambda(+)(c) lifetime
PHYSICAL REVIEW LETTERS
2001; 86 (11): 2232-2236
Abstract
The Lambda+c lifetime is measured using 9.0 fb(-1) of e+e- annihilation data collected on or just below the Upsilon(4S) resonance with the CLEO II.V detector at CESR. Using an unbinned maximum likelihood fit, the Lambda+c lifetime is measured to be 179.6+/-6.9(stat)+/-4.4(syst) fs. The precision of this colliding beam measurement is comparable to other measurements, which are based on fixed-target experiments, with different systematic uncertainties.
View details for Web of Science ID 000167445200011
View details for PubMedID 11289897
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Search for a scalar bottom quark with mass 3.5-4.5 GeV/c(2)
PHYSICAL REVIEW D
2001; 63 (5)
View details for Web of Science ID 000167258000001
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First observation of the Sigma(*+)(c) baryon and a new measurement of the Sigma(*+)(c) mass
PHYSICAL REVIEW LETTERS
2001; 86 (7): 1167-1170
Abstract
Using data recorded with the CLEO II and CLEO II.V detector configurations at the Cornell Electron Storage Rings, we report the first observation and mass measurement of the Sigma(*+)(c) charmed baryon, and an updated measurement of the mass of the Sigma(+)(c) baryon. We find M(Sigma(*+)(c))-M(Lambda(+)(c)) = (231.0+/-1.1+/-2.0) MeV, and M(Sigma(+)(c))-M(Lambda(+)(c)) = (166.4+/-0.2+/-0.3) MeV, where the errors are statistical and systematic, respectively.
View details for Web of Science ID 000166907600006
View details for PubMedID 11178035
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Study of chi(c1) and chi(c2) meson production in B meson decays
PHYSICAL REVIEW D
2001; 63 (3)
View details for Web of Science ID 000166750100002
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Study of B ->psi(2S) K and B ->psi(2S) K*(892) decays
PHYSICAL REVIEW D
2001; 63 (3)
View details for Web of Science ID 000166750100003
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Study of B decays to charmonium states: B -> eta K-c and B -> chi K-c0
PHYSICAL REVIEW LETTERS
2001; 86 (1): 30-34
View details for Web of Science ID 000166192800008
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Measurement of B ->(Ds(*)+D*(*)) branching fractions
PHYSICAL REVIEW D
2000; 62 (11)
View details for Web of Science ID 000165612800007
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Search for decays of B-0 mesons into pairs of leptons: B-0 -> e(+)e(-), B-0 ->mu(+)mu(-), and B-0 -> e(+/-)mu(-/+)
PHYSICAL REVIEW D
2000; 62 (9)
View details for Web of Science ID 000165111400002
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Measurement of the product branching fraction B(c ->Theta X-c) x B(Theta(c)->Lambda X)
PHYSICAL REVIEW D
2000; 62 (9)
View details for Web of Science ID 000165111400011
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Measurements of the mass, total width, and two-photon partial width of the eta(c) meson
PHYSICAL REVIEW LETTERS
2000; 85 (15): 3095-3099
Abstract
Using 13.4 fb(-1) of data collected with the CLEO detector at the Cornell Electron Storage Ring, we have observed 300 events for the two-photon production of ground-state pseudoscalar charmonium in the decay eta(c)-->K(0)(S)K-/+pi(+/-). We have measured the eta(c) mass to be [2980.4+/-2.3 (stat)+/-0.6 (syst)] MeV and its full width as [27.0+/-5.8 (stat)+/-1.4 (syst)] MeV. We have determined the two-photon partial width of the eta(c) meson to be [7.6+/-0.8 (stat)+/-0.4 (syst)+/-2.3 (br)] keV, with the last uncertainty associated with the decay branching fraction.
View details for Web of Science ID 000089807800008
View details for PubMedID 11019275
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Study of charmless hadronic B meson decays to pseudoscalar-vector final states
PHYSICAL REVIEW LETTERS
2000; 85 (14): 2881-2885
Abstract
We report results of searches for charmless hadronic B meson decays to pseudoscalar( pi(+/-), K+/-, pi(0), or K(0)(S))-vector( rho, K(*), or omega) final states. By using 9.7x10(6) BB pairs collected with the CLEO detector, we report the first observation of B(-)--->pi(-)rho(0), B(0)-->pi(+/-)rho(-/+), and B(-)-->pi(-)omega, which are expected to be dominated by hadronic b-->u transitions. The measured branching fractions are (10.4(+3.3)(-3.4)+/-2.1)x10(-6), (27.6(+8.4)(-7.4)+/-4.2)x10(-6), and (11.3(+3.3)(-2.9)+/-1. 4)x10(-6), respectively. Branching fraction upper limits are set for all of the other decay modes investigated.
View details for PubMedID 11005959
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Measurements of charm fragmentation into D-s(*+) and D-s(+) in e(+)e(-) annihilations at root s=10.5 GeV
PHYSICAL REVIEW D
2000; 62 (7)
View details for Web of Science ID 000089749400010
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Resonance structure of tau(-)-> K-pi(+)pi(-)nu(tau) decays
PHYSICAL REVIEW D
2000; 62 (7)
View details for Web of Science ID 000089749400013
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Measurement of B(Lambda(+)(c)-> pK(-)pi(+))
PHYSICAL REVIEW D
2000; 62 (7)
View details for Web of Science ID 000089749400012
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Precise measurement of B-0-(B-0)over-bar mixing parameters at the Epsilon(4S)
PHYSICS LETTERS B
2000; 490 (1-2): 36-44
View details for Web of Science ID 000089653700006
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Study of exclusive two-body B-omicron meson decays to charmonium
PHYSICAL REVIEW D
2000; 62 (5)
View details for Web of Science ID 000089022500001
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Study of the decays B-0 -> D(*)+ D(*)-
PHYSICAL REVIEW D
2000; 62 (3)
View details for Web of Science ID 000088516300008
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Two-body B meson decays to eta and eta ': Observation of B ->eta K
PHYSICAL REVIEW LETTERS
2000; 85 (3): 520-524
Abstract
In a sample of 19 x 10(6) produced B mesons, we have observed the decays B-->eta K(*) and improved our previous measurements of B-->eta'K. The branching fractions we measure for these decay modes are B(B+-->eta K(*+)) = (26.4(+9.6)(-8.2)+/-3.3)x10(-6), B(B(0)-->eta K(*0)) = (13.8(+5.5)(-4.6)+/-1.6)x10(-6), B(B(+)-->eta'K(+) = (80(+10)(-9)+/-7)x10(-6), and B(B(0)-->eta'K0) = (89(+18)(-16)+/-9)x10(-6). We have searched with comparable sensitivity for related decays and report upper limits for these branching fractions.
View details for Web of Science ID 000088179900011
View details for PubMedID 10991330
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Observation of B -> K-+/-pi(0) and B -> K-0 pi(0) and evidence for B ->pi(+)pi(-)
PHYSICAL REVIEW LETTERS
2000; 85 (3): 515-519
Abstract
We have studied charmless hadronic decays of B mesons into two-body final states with kaons and pions and observe three new processes with the following branching fractions: beta(B-->pi(+)pi(-)) = (4.3(+1. 6)(-1.4)+/-0.5)x10(-6), beta(B-->K(0)pi(0)) = (14.6(+5.9+2.4)(-5.1-3. 3))x10(-6), and beta(B-->K(+)/-pi(0)) = (11.6(+3.0+1.4)(-2.7-1.3))x10(-6). We also update our previous measurements for the decays B-->K(+)/-pi(-/+) and B+/--->K(0)pi(+/-).
View details for Web of Science ID 000088179900010
View details for PubMedID 10991329
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Measurement of charge asymmetries in charmless hadronic B meson decays
PHYSICAL REVIEW LETTERS
2000; 85 (3): 525-529
Abstract
We search for CP-violating charge asymmetries (alpha(CP)) in the B meson decays to K(+/-)pi(-/+), K(+/-)pi(0), K(0)(S)pi(+/-), K(+/-)eta('), and omega pi(+/-). Using 9.66 million upsilon(4S) decays collected with the CLEO detector, the statistical precision on alpha(CP) is in the range of +/-0.12 to +/-0.25 depending on decay mode. While CP-violating asymmetries of up to +/-0.5 are possible within the standard model, the measured asymmetries are consistent with zero in all five decay modes studied.
View details for Web of Science ID 000088179900012
View details for PubMedID 10991331
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Search for CP violation in B-+/--> J/psi K-+/- and B-+/-->psi(2S)K-+/- decays
PHYSICAL REVIEW LETTERS
2000; 84 (26): 5940-5944
Abstract
We present a search for direct CP violation in B+/--->J/psiK+/- and B+/--->psi(2S)K+/- decays. In a sample of 9.7x10(6) B&Bmacr; meson pairs collected with the CLEO detector, we have fully reconstructed 534 B+/--->J/psiK+/- and 120 B+/--->psi(2S)K+/- decays with very low background. We have measured the CP-violating charge asymmetry to be [+1.8+/-4.3(stat)+/-0.4(syst)]% for B+/--->J/psiK+/- and [+2.0+/-9. 1(stat)+/-1.0(syst)]% for B+/--->psi(2S)K+/-.
View details for Web of Science ID 000087909500006
View details for PubMedID 10991094
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Study of exclusive radiative B meson decays
PHYSICAL REVIEW LETTERS
2000; 84 (23): 5283-5287
View details for Web of Science ID 000087411600012
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Measurement of the B-0 and B+ meson masses from B-0 ->psi((')) K-S(0) and B+->psi((')) K+ decays
PHYSICAL REVIEW D
2000; 61 (11)
View details for Web of Science ID 000087284800001
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Hadronic structure in the decay tau(-)->pi(-)pi(0)nu(tau)
PHYSICAL REVIEW D
2000; 61 (11)
View details for Web of Science ID 000087284800009
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Search for D-0-(0) mixing
PHYSICAL REVIEW LETTERS
2000; 84 (22): 5038-5042
View details for Web of Science ID 000087266300003
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Search for the decay (B)over-bar(0) -> D*(0)gamma
PHYSICAL REVIEW LETTERS
2000; 84 (19): 4292-4295
View details for Web of Science ID 000086941600010
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Charged track multiplicity in B meson decay
PHYSICAL REVIEW D
2000; 61 (7)
View details for Web of Science ID 000086065200010
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Resonant structure of tau -> 3 pi pi(0)nu(tau) and tau ->omega pi nu(tau) decays
PHYSICAL REVIEW D
2000; 61 (7)
View details for Web of Science ID 000086065200011
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Update of the search for the neutrinoless decay tau ->mu gamma
PHYSICAL REVIEW D
2000; 61 (7)
View details for Web of Science ID 000086065200001
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Measurement of B ->rho l nu decay and vertical bar V-ub vertical bar
PHYSICAL REVIEW D
2000; 61 (5)
View details for Web of Science ID 000085685600004
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Limit on the tau neutrino mass from tau(-)->pi(-)pi(+)pi(-)pi(0)nu(tau)
PHYSICAL REVIEW D
2000; 61 (5)
View details for Web of Science ID 000085685600005
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Structure functions in the decay tau(-/+)->pi(-/+)pi(0)pi(0)nu(tau)
PHYSICAL REVIEW D
2000; 61 (5)
View details for Web of Science ID 000085685600007
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Type Ia supernovae, evolution, and the cosmological constant
ASTROPHYSICAL JOURNAL
2000; 530 (2): 593-617
View details for Web of Science ID 000086062500004
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First observation of the decay B -> J/psi Phi K
PHYSICAL REVIEW LETTERS
2000; 84 (7): 1393-1397
View details for Web of Science ID 000085267100009
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Observation of radiative leptonic decay of the tau lepton
PHYSICAL REVIEW LETTERS
2000; 84 (5): 830-834
View details for Web of Science ID 000085005700010
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Search for rare and forbidden eta ' decays
PHYSICAL REVIEW LETTERS
2000; 84 (1): 26-30
View details for Web of Science ID 000084587900007
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Hadronic structure in the decay tau(-) -> nu(tau)pi(-) pi(0) pi(0) and the sign of the tau neutrino helicity
PHYSICAL REVIEW D
2000; 61 (1)
View details for Web of Science ID 000084674200005
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Study of 3-prong hadronic tau decays with charged kaons
PHYSICAL REVIEW D
1999; 60 (11)
View details for Web of Science ID 000084138100009
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Evidence of new states decaying into Xi(*)(c)pi
PHYSICAL REVIEW LETTERS
1999; 83 (17): 3390-3393
View details for Web of Science ID 000083242800011
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Measurement of charm meson lifetimes
PHYSICAL REVIEW LETTERS
1999; 82 (23): 4586-4590
View details for Web of Science ID 000080682300005
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Search for exclusive rare baryonic decays of B mesons
PHYSICAL REVIEW D
1999; 59 (11)
View details for Web of Science ID 000080778900001
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Measurement of the B -> Dl nu branching fractions and form factor
PHYSICAL REVIEW LETTERS
1999; 82 (19): 3746-3750
View details for Web of Science ID 000080207500005
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Search for baryon and lepton number violating decays of the tau lepton
PHYSICAL REVIEW D
1999; 59 (9)
View details for Web of Science ID 000080114600003
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First observation of the decay B-0 -> D*D+*(-)
PHYSICAL REVIEW LETTERS
1999; 82 (15): 3020-3024
View details for Web of Science ID 000079646200005
- Upsilon dipion transitions at energies near the Upsilon(4S) PHYSICAL REVIEW D