A5020716271- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- High-Energy Particle Collisions Research
- Pulsars and Gravitational Waves Research
- Dark Matter and Cosmic Phenomena
- Astrophysical Phenomena and Observations
- Neutrino Physics Research
- Black Holes and Theoretical Physics
- Radio Astronomy Observations and Technology
- Galaxies: Formation, Evolution, Phenomena
- Atomic and Subatomic Physics Research
- Cosmology and Gravitation Theories
- Particle Accelerators and Free-Electron Lasers
- Astronomical Observations and Instrumentation
- Particle Detector Development and Performance
- Geophysics and Gravity Measurements
- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- Radiation Detection and Scintillator Technologies
- Superconducting Materials and Applications
- Medical Imaging Techniques and Applications
- Astronomy and Astrophysical Research
- High-pressure geophysics and materials
University of Chinese Academy of Sciences
2021-2025
Southwest Jiaotong University
2021-2025
Anhui University of Science and Technology
2025
Chinese Academy of Sciences
2015-2024
Institute of High Energy Physics
2023-2024
South China University of Technology
2024
Yunnan Observatories
2015-2024
Siberian Branch of the Russian Academy of Sciences
2024
China University of Geosciences
2024
Carnegie Mellon University
2024
This catalog summarizes 117 high-confidence ⩾0.1 GeV gamma-ray pulsar detections using three years of data acquired by the Large Area Telescope (LAT) on Fermi satellite. Half are neutron stars discovered LAT through periodicity searches in and radio around unassociated source positions. The pulsars evenly divided into groups: millisecond pulsars, young radio-loud radio-quiet pulsars. We characterize pulse profiles energy spectra derive luminosities when distance information exists. Spectral...
The gamma-ray sky >100 MeV is dominated by the diffuse emissions from interactions of cosmic rays with interstellar gas and radiation fields Milky Way. Observations these provide a tool to study cosmic-ray origin propagation, medium. We present measurements first 21 months Fermi-LAT mission compare models emission generated using GALPROP code. are fitted data incorporate astrophysical input for distribution sources, fields. To assess uncertainties associated input, grid created varying...
The second catalog of active galactic nuclei (AGNs) detected by the Fermi Large Area Telescope (LAT) in two years scientific operation is presented. LAT AGN (2LAC) includes 1017 γ-ray sources located at high Galactic latitudes (|b| > 10°) that are with a test statistic (TS) greater than 25 and associated statistically AGNs. However, some these affected analysis issues multiple Consequently, we define Clean Sample which 886 AGNs, comprising 395 BL Lacertae objects (BL Lac objects), 310...
The Fermi Large Area Telescope (Fermi-LAT, hereafter LAT), the primary instrument on Gamma-ray Space (Fermi) mission, is an imaging, wide field-of-view, high-energy γ-ray telescope, covering energy range from 20 MeV to more than 300 GeV. During first years of LAT team has gained considerable insight into in-flight performance instrument. Accordingly, we have updated analysis used reduce data for public release as well response functions (IRFs), description provided analysis. In this paper,...
We present an incremental version (4FGL-DR3, for Data Release 3) of the fourth Fermi-LAT catalog gamma-ray sources. Based on first twelve years science data in energy range from 50 MeV to 1 TeV, it contains 6658 The analysis improves that used 4FGL over eight data: more sources are fit with curved spectra, we introduce a robust spectral parameterization pulsars, and extend points TeV. parameters, distributions, associations updated all Light curves rebuilt yr intervals (not 2 month...
The Fermi bubbles are two large structures in the gamma-ray sky extending to 55° above and below Galactic center. We analyze 50 months of Large Area Telescope data between 100 MeV 500 GeV 10° latitude derive spectrum morphology bubbles. thoroughly explore systematic uncertainties that arise when modeling diffuse emission through separate approaches. is well described by either a log parabola or power law with an exponential cutoff. exclude simple more than 7σ significance. cutoff has index...
In three years of observations since the beginning nominal science operations in August 2008, Large Area Telescope (LAT) on board Fermi Gamma Ray Space has observed high-energy (>20 MeV) \gamma-ray emission from 35 gamma-ray bursts (GRBs). Among these, 28 GRBs have been detected above 100 MeV and 7 ~ 20 MeV. The first Fermi-LAT catalog is a compilation these detections provides systematic study for time. To generate catalog, we examined 733 by Gamma-Ray Burst Monitor (GBM) processed each...
ABSTRACT Most of the celestial γ rays detected by Large Area Telescope (LAT) on board Fermi Gamma-ray Space originate from interstellar medium when energetic cosmic interact with nucleons and photons. Conventional point-source extended-source studies rely modeling this diffuse emission for accurate characterization. Here, we describe development Galactic Interstellar Emission Model (GIEM), which is standard adopted LAT Collaboration publicly available. This model based a linear combination...
Weakly interacting massive particles (WIMPs) are a theoretical class of that excellent dark matter candidates. WIMP annihilation or decay may produce essentially monochromatic γ rays detectable by the Fermi Large Area Telescope (LAT) against astrophysical γ-ray emission Galaxy. We have searched for spectral lines in energy range 5–300 GeV using 3.7 years data, reprocessed with updated instrument calibrations and an improved dispersion model compared to previous Fermi-LAT Collaboration line...
High-energy photons from the Crab Nebula The contains a pulsar that excites surrounding gas to emit high-energy radiation. combination of pulsar's youth and nearby location makes nebula brightest gamma-ray source in sky. LHAASO Collaboration report observations this at energies tera– peta–electron volts, extending spectrum prototypical object. They combine these data with lower model physics emission process. multiwave-length can be explained by synchrotron radiation inverse Compton...
Some gamma-ray bursts (GRBs) have a tera-electron volt (TeV) afterglow, but the early onset of this has not been observed. We report observations with Large High Altitude Air Shower Observatory (LHAASO) bright GRB 221009A, which serendipitously occurred within instrument's field view. More than 64,000 photons >0.2 TeV were detected first 3000 seconds. The flux began several minutes after trigger and then rose to peak ~10 seconds later. This was followed by decay phase, became more rapid ~650...
Abstract We present the first catalog of very-high-energy and ultra-high-energy gamma-ray sources detected by Large High Altitude Air Shower Observatory. The was compiled using 508 days data collected Water Cherenkov Detector Array from 2021 March to 2022 September 933 recorded Kilometer Squared 2020 January September. This represents main result most sensitive large coverage survey sky above 1 TeV, covering decl. −20° 80°. In total, contains 90 with an extended size smaller than 2° a...
Abstract We report the discovery of GRB 221009A, highest flux gamma-ray burst (GRB) ever observed by Fermi Gamma-ray Burst Monitor (Fermi-GBM). This has continuous prompt emission lasting more than 600 s, which smoothly transitions to afterglow visible in Fermi-GBM energy range (8 keV–40 MeV), and total energetics higher any other sample. By using a variety new existing analysis techniques we probe spectral temporal evolution 221009A. find no prior trigger time ( t 0 ; 2022 October 9 at...
Abstract We present 294 pulsars found in GeV data from the Large Area Telescope (LAT) on Fermi Gamma-ray Space Telescope. Another 33 millisecond (MSPs) discovered deep radio searches of LAT sources will likely reveal pulsations once phase-connected rotation ephemerides are achieved. A further dozen optical and/or X-ray binary systems colocated with also harbor gamma-ray MSPs. This catalog thus reports roughly 340 and candidates, 10% all known pulsars, compared to ≤11 before Fermi. Half...
The diffuse Galactic γ-ray emission, mainly produced via interactions between cosmic rays and the interstellar medium and/or radiation field, is a very important probe of distribution, propagation, interaction in Milky Way. In this Letter, we report measurements γ from plane 10 TeV 1 PeV energies, with square kilometer array Large High Altitude Air Shower Observatory (LHAASO). Diffuse emissions inner (15°<l<125°, |b|<5°) outer (125°<l<235°, are detected 29.1σ 12.7σ significance,...
The Fermi Large Area Telescope (LAT) light curve repository (LCR) is a publicly available, continually updated library of gamma-ray curves variable Fermi-LAT sources generated over multiple timescales. LCR aims to provide publication-quality binned on timescales 3 days, 7 and 30 days for 1525 deemed in the source catalog first 10 years observations. consists through full likelihood analyses that model surrounding region, providing fluxes photon indices each time bin. intended as resource...
Abstract The Einstein Probe (EP) is an interdisciplinary mission of time-domain and X-ray astronomy. Equipped with a wide-field lobster-eye focusing imager, EP will discover cosmic transients monitor the variability known sources in 0.5–4 keV, at combination detecting sensitivity cadence that not accessible to previous current monitoring missions. can perform quick characterisation or outbursts Wolter-I telescope onboard. In this paper, science objectives are presented. expected enlarge...
GRB110721A was observed by the Fermi Gamma-ray Space Telescope using its two instruments Large Area (LAT) and Burst Monitor (GBM). The burst consisted of one major emission episode which lasted for ~24.5 seconds (in GBM) had a peak flux 5.7\pm0.2 x 10^{-5} erg/s/cm^2. time-resolved spectrum is best modeled with combination Band function blackbody spectrum. energy component initially 15\pm2 MeV, highest value ever detected in GRB. This measurement made possible combining GBM/BGO data LAT Low...
ABSTRACT To uniformly determine the properties of supernova remnants (SNRs) at high energies, we have developed first systematic survey energies from 1 to 100 GeV using data Fermi Large Area Telescope (LAT). Based on spatial overlap sources detected with SNRs known radio surveys, classify 30 as likely SNRs. We also report 14 marginal associations and 245 flux upper limits. A mock catalog in which positions are scrambled Galactic longitude allows us an limit 22% number candidates falsely...
The Fermi Large Area Telescope (LAT) observed two bright X-class solar flares on 2012 March 7, and detected gamma-rays up to 4 GeV. We both during the impulsive temporally-extended emission phases, with above 100 MeV lasting for approximately 20 hours. Accurate localization of gamma-ray production site(s) coincide active region from which X-ray emissions associated these originated. Our analysis >100 shows a relatively rapid monotonic decrease in flux first hour phase, much slower, almost...
The contribution of unresolved sources to the diffuse gamma-ray background could induce anisotropies in this emission on small angular scales. We analyze power spectrum measured by Fermi LAT at Galactic latitudes |b| > 30 deg four energy bins spanning 1 50 GeV. At multipoles \ell \ge 155, corresponding scales \lesssim 2 deg, above photon noise level is detected >99.99% CL 1-2 GeV, 2-5 and 5-10 GeV bins, >99% 10-50 Within each bin takes approximately same value all suggesting that it...
The Fermi Large Area Telescope First Source Catalog (1FGL) provided spatial, spectral, and temporal properties for a large number of gamma-ray sources using uniform analysis method. After correlating with the most-complete catalogs source types known to emit gamma rays, 630 these are "unassociated" (i.e. have no obvious counterparts at other wavelengths). Here, we employ two statistical analyses primary characteristics unassociated in an effort correlate their AGN pulsar populations 1FGL....
Numerical simulations based on the Lambda-CDM model of cosmology predict a large number as yet unobserved Galactic dark matter satellites. We report results Large Area Telescope (LAT) search for these satellites via gamma-ray emission expected from annihilation weakly interacting massive particle (WIMP) matter. Some are to have hard spectra, finite angular extents, and lack counterparts at other wavelengths. sought identify LAT sources with characteristics, focusing spectra consistent WIMP...