Gamma ray astrophysics: the EGRET results

Abstract

Cosmic gamma rays provide insight into some of the most dynamic processes in the Universe. At the dawn of a new generation of gamma-ray telescopes, this review summarizes results from the Energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory, the principal predecessor mission studying high-energy photons in the 100 MeV energy range. EGRET viewed a gamma-ray sky dominated by prominent emission from the Milky Way, but featuring an array of other sources, including quasars, pulsars, gamma-ray bursts, and many sources that remain unidentified. A central feature of the EGRET results was the high degree of variability seen in many gamma-ray sources, indicative of the powerful forces at work in objects visible to gamma-ray telescopes.

23 pages, 24 figures

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• The ATNF Pulsar Catalogue
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• Cosmological dark matter annihilations into gamma-rays - a closer look
• 3.9 day orbital modulation in the TeV gamma-ray flux and spectrum from the X-ray binary LS 5039
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• The Crab pulsar in the 0.75-30 MeV range as seen by CGRO COMPTEL
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• EGRET upper limits on the high-energy gamma-ray emission of galaxy clusters
• Multi-Epoch VLBA Observations of EGRET-Detected Quasars and BL Lac Objects: Connection between Superluminal Ejections and Gamma-Ray Flares in Blazars
• The Starburst Contribution to the Extra-Galactic Gamma-Ray Background
• Cosmic Ray Protons and Magnetic Fields in Clusters of Galaxies and their Cosmological Consequences
• Variability of EGRET Gamma-Ray Sources
• PSR J2229+6114: Discovery of an Energetic Young Pulsar in the Error Box of the EGRET Source 3EG J2227+6122
• Multi-Epoch Multiwavelength Spectra and Models for Blazar 3C~279
• Supernova remnants and gamma-ray sources
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• The Guaranteed Gamma-Ray Background
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• Gamma-Ray Pulsars and Massive Stars in the Solar Neighborhood
• GeV emission from the nearby radio galaxy Centaurus A
• Gamma Ray Pulsars: Multiwavelength Observations
• Blazar Counterparts for 3EG Sources at -40 < decl. < 0: Pushing South Through the Bulge
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• The Likely Cause of the EGRET GeV Anomaly and its Implications
• Broadband Spectral Analysis of PKS 0528+134: A Report on Six Years of EGRET Observations
• EGRET Gamma-Ray Blazars: Luminosity Function and Contribution to the Extragalactic Gamma-Ray Background
• Is the EGRET source 3EG J1621+8203 the radio galaxy NGC 6251?
• Does the Blazar Gamma-Ray Spectrum Harden with Increasing Flux? Analysis of 9 Years of EGRET Data
• A Neutron-Star Identification for the High-Energy Gamma-ray Source 3EG J1835+5918 Detected in the ROSAT All-Sky Survey
• High resolution spatial and timing observations of millisecond pulsar PSR J0218+4232 with Chandra
• The Next Geminga: Deep Multiwavelength Observations of a Neutron Star Identified with 3EG J1835+5918
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• Is the dark matter interpretation of the EGRET gamma excess compatible with antiproton measurements?
• The Geminga Fraction
• Discovery of a non-blazar gamma-ray transient near the Galactic plane: GRO J1838-04
• A Systematic Search for Short-term Variability of EGRET Sources
• The Extragalactic Gamma Ray Background
• EGRET upper limits and stacking searches of gamma-ray observations of luminous and ultra-luminous infrared galaxies
• Is 3C111, an apparently normal radio galaxy, the counterpart of 3EG J0416+3650?
• The Earth's Gamma-ray Albedo as observed by EGRET
• The Gamma-Ray Properties of Unidentified EGRET Sources
• Pulsar Slot Gaps and Unidentified EGRET Sources
• Egret (GeV) Blazars

Cited by in corpus (44)

• The Second Fermi Large Area Telescope Catalog of Gamma-ray Pulsars
• Indirect search for dark matter with micrOMEGAs2.4
• Detection of 16 Gamma-Ray Pulsars Through Blind Frequency Searches Using the Fermi LAT
• Detection of 107 glitches in 36 southern pulsars
• The Third Fermi Large Area Telescope Catalog of Gamma-ray Pulsars
• Eight gamma-ray pulsars discovered in blind frequency searches of Fermi LAT data
• Classification and Ranking of Fermi LAT Gamma-ray Sources from the 3FGL Catalog using Machine Learning Techniques
• The Pulsar Contribution to the Gamma-Ray Background
• A multiwavelength study on the high-energy behaviour of Fermi/LAT pulsars
• The Extragalactic Gamma-ray Sky in the Fermi era
• Pulsar searches of Fermi unassociated sources with the Effelsberg telescope
• Discovery of Pulsed $\gamma$-rays from PSR J0034-0534 with the Fermi LAT: A Case for Co-located Radio and $\gamma$-ray Emission Regions
• The Gamma-ray Blazar Quest: new optical spectra, state of art and future perspectives
• On the pulse--width statistics in radio pulsars. I. Importance of the interpulse emission
• Wide radio beams from gamma-ray pulsars
• Counting gamma rays in the directions of galaxy clusters
• Fermi Gamma-ray Space Telescope: High-Energy Results from the First Year
• Discovery of a faint X-ray counterpart and of a parsec-long X-ray tail for the middle-aged, gamma-ray only pulsar PSR J0357+3205
• Extending the Event-weighted Pulsation Search to Very Faint Gamma-ray Sources
• Gamma rays from the Galactic Centre region: a review
• Fermi Large Area Telescope Observations of Gamma-ray Pulsars PSR J1057-5226, J1709-4429, and J1952+3252
• Absorption of 10 Gev--1 Tev Gamma Rays from 3C 279
• 0FGL J1830.3+0617: A Fermi Blazar Near the Galactic Plane
• Clusters of Black Holes as Point-Like Gamma-ray Sources
• Measurement of redshift dependent cross correlation of HSC clusters and Fermi $\gamma$ rays
• VLT observations of the two Fermi pulsars PSR J1357-6429 and PSR J1048-5832
• Observations of three young gamma-ray pulsars with the Gran Telescopio Canarias
• VLT Suzaku observations of the Fermi pulsar PSR J1028-5819
• Locating positions of γ-ray--emitting regions in blazars
• Lower bounds of altitudes for pulsar $\gamma$-ray radiation
• Phase resolved spectrum of the Crab pulsar from NICER
• Differences between radio-loud and radio-quiet gamma-ray pulsars as revealed by Fermi
• Search for differences between radio-loud and radio-quiet gamma-ray pulsar populations with Fermi-LAT data
• Deep optical imaging of the gamma-ray pulsar J1048-5832 with the VLT
• Decaying Fermionic Dark Matter Search with CALET
• Black hole dynamical evolution in a Lorentz-violating spacetime
• Beyond the 2nd Fermi Pulsar Catalog
• Fermi-LAT searches for gamma-ray pulsars
• Detecting and characterizing pulsar haloes with the Cherenkov Telescope Array
• Identification of Candidate Millisecond Pulsars from Fermi LAT Observations
• Gamma Ray and Neutrino Flux from Annihilation of Neutralino Dark Matter at Galactic Halo Region in mAMSB Model
• Very Long Baseline Interferometry Observations of the Proposed Radio Counterpart of an EGRET Source
• Probing mixed-state dark matter and flavor observables in a scalar-assisted baryonic gauge theory
• Pair Production Detectors for Gamma-ray Astrophysics