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Related papers: Fermi observations of TeV-selected AGN

200 papers

The detection of very-high-energy (VHE; $>$100 GeV) $\gamma$-ray radiation from misaligned jetted Active Galactic Nuclei (AGN) challenges the emission models that primarily explain VHE emissions from beamed AGN, i.e., blazars. Using over 16…

High Energy Astrophysical Phenomena · Physics 2025-08-25 Gunjan Tomar , Vaidehi S. Paliya , D. J. Saikia , C. S. Stalin

Very high-energy (VHE; E>100 GeV) gamma-rays have been detected from a wide range of astronomical objects, such as pulsar wind nebulae (PWNe), supernova remnants (SNRs), giant molecular clouds, gamma-ray binaries, the Galactic Center,…

High Energy Astrophysical Phenomena · Physics 2015-03-13 P. H. Thomas Tam , Stefan Wagner , Omar Tibolla , Ryan Chaves

We present an incremental version (4FGL-DR2, for Data Release 2) of the fourth Fermi-LAT catalog of gamma-ray sources. Based on the first ten years of science data in the energy range from 50 MeV to 1 TeV, it uses the same analysis methods…

High Energy Astrophysical Phenomena · Physics 2020-12-18 J. Ballet , T. H. Burnett , S. W. Digel , B. Lott

Following its launch in June 2008, the Fermi Gamma-ray Space Telescope (Fermi) began a sky survey in August. The Large Area Telescope (LAT) on Fermi in 3 months produced a deeper and better-resolved map of the gamma-ray sky than any…

High Energy Astrophysical Phenomena · Physics 2009-07-06 A. A. Abdo

We investigate the spectroscopic optical properties of gamma-ray sources detected with high significance above 50 GeV in the Third Catalog of Hard Fermi-LAT Sources (3FHL) and that are good candidates as TeV emitters. We focus on the 91…

Astrophysics of Galaxies · Physics 2020-07-08 Simona Paiano , Renato Falomo , Aldo Treves , Riccardo Scarpa

We present a catalog of sources of very high energy (E>100 GeV) gamma-rays detected by the Large Area Telescope (LAT) onboard the Fermi Gamma-Ray Space Telescope at Galactic latitudes |b|>=10 degrees. We cross-correlate the directions of…

High Energy Astrophysical Phenomena · Physics 2015-05-18 A. Neronov , D. V. Semikoz , Ie. Vovk

The Fermi observatory, with its Gamma-Ray Bursts monitor (GBM) and Large Area Telescope (LAT), is observing Gamma-ray Bursts with unprecedented spectral coverage and sensitivity, from ~10 keV to > 300 GeV. In the first 3 years of the…

High Energy Astrophysical Phenomena · Physics 2013-05-27 Giacomo Vianello

The Large Area Telescope (LAT) aboard the Fermi satellite allows us to study the high-energy gamma-ray sky with unprecedented sensitivity. However, the origin of 31% of the detected gamma-ray sources remains unknown. This population of…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Hannes-S. Zechlin , Dieter Horns

The Fermi Large Area Telescope (LAT) has made the first definitive GeV detections of the binaries LS I +61^{\circ}303 and LS5039 in the first year after its launch in August 2008. These detections were unambiguous because, apart from a…

High Energy Astrophysical Phenomena · Physics 2019-08-14 D. Hadasch

The synergy between the Fermi-LAT and ground-based Cherenkov telescope arrays gives us the opportunity for the first time to characterize the high-energy emission from blazars over 5 decades in energy, from 100 MeV to 10 TeV. In this study,…

High Energy Astrophysical Phenomena · Physics 2015-06-12 G. D. Senturk , M. Errando , M. Boettcher , R. Mukherjee

We focus our analysis on 55 BL Lac objects with a hard Fermi gamma-ray spectrum, and for which a redshift or a lower limit to it has been determined by a previous study of ours. We extrapolate the spectral fits given by the 4FGL catalogue…

High Energy Astrophysical Phenomena · Physics 2021-10-20 Simona Paiano , Aldo Treves , Alberto Franceschini , Renato Falomo

The synergy between the Fermi-LAT and ground-based Cherenkov telescope arrays gives us the opportunity for the first time to characterize the high energy emission (100 MeV - 10 TeV) from more than 30 blazars. In this study we performed a…

High Energy Astrophysical Phenomena · Physics 2011-11-03 G. D. Senturk , M. Errando , M. Boettcher , P. Coppi , R. Mukherjee , P. Roustazadeh

Variability is a prominent observational feature of blazars. The high-energy radiation mechanism of jets has always been important but still unclear. In this work, we performed a detailed analysis using Fermi-LAT data across 15 years and…

High Energy Astrophysical Phenomena · Physics 2023-12-05 Gege Wang , Hubing Xiao , Junhui Fan , Xin Zhang

We present a catalog of gamma-ray sources at energies above 10 GeV based on data from the Large Area Telescope (LAT) accumulated during the first three years of the Fermi Gamma-ray Space Telescope mission. The first Fermi-LAT catalog of…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 LAT Collaboration

The Fermi-Large Area Telescope (LAT) First Source Catalog (1FGL) was released in February 2010 and the Fermi-LAT 2-Year Source Catalog (2FGL) appeared in April 2012, based on data from 24 months of operation. Since their releases, many…

The launch of the Fermi satellite in 2008, with its Large Area Telescope (LAT) on board, has opened a new era for the study of gamma-ray sources at GeV ($10^9$ eV) energies. Similarly, the commissioning of the third generation of imaging…

Instrumentation and Methods for Astrophysics · Physics 2023-11-07 Denys Malyshev , Lars Mohrmann

Blazars are a subclass of active galactic nuclei (AGN) having relativistic jets aligned within a few degrees of our line-of-sight and form the majority of the AGN detected in the TeV regime. The Fermi-Large Area Telescope (LAT) is a…

High Energy Astrophysical Phenomena · Physics 2023-07-04 Atreya Acharyya , Alberto C. Sadun

The Fermi Large Area Telescope (LAT) has detected thousands of sources since its launch in 2008, with many remaining unidentified. Some of these point sources may arise from source confusion. Specifically, there could be extended sources…

High Energy Astrophysical Phenomena · Physics 2025-04-07 Giovanni Cozzolongo , Alison M. W. Mitchell , Samuel T. Spencer , Dmitry Malyshev , Tim Unbehaun

We report the results of an analysis to identify candidates for very high energy (VHE; E > 100 GeV) emission from high-latitude (|b|>10) unassociated sources in the year-1 catalog under development by the Fermi large area telescope (LAT)…

High Energy Astrophysical Phenomena · Physics 2019-08-14 P. Fortin , D. Horan , E. Ferrara

The first Fermi Large Area Telescope (LAT) catalogue of sources (1FHL) emitting at high energies (above 10 GeV) reports the details of 514 objects detected in the first three years of the Fermi mission. Of these, 71 were reported as…

High Energy Astrophysical Phenomena · Physics 2015-06-24 R. Landi , L. Bassani , J. B. Stephen , N. Masetti , A. Malizia , P. Ubertini