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Related papers: Fermi observations of TeV-selected AGN

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We report on gamma-ray analysis of the region containing the bright TeV source HESS J1640-465 and the close-by TeV source HESS J1641-463 using 64 months of observations with the Fermi Large Area Telescope (LAT). Previously only one GeV…

High Energy Astrophysical Phenomena · Physics 2015-06-22 M. Lemoine-Goumard , M. -H. Grondin , F. Acero , J. Ballet , H. Laffon , T. Reposeur

Gamma-ray Bursts (GRB) were discovered by satellite-based detectors as powerful sources of transient $\gamma$-ray emission. The Fermi satellite detected an increasing number of these events with its dedicated Gamma-ray Burst Monitor (GBM),…

Instrumentation and Methods for Astrophysics · Physics 2021-09-29 G. La Mura , U. Barres de Almeida , R. Conceição , A. De Angelis , F. Longo , M. Pimenta , E. Prandini , E. Ruiz-Velasco , B. Tomé

The quest to uncover periodic patterns within the $\gamma$-ray emissions of jetted active galactic nuclei (AGN) has recently emerged as a focal point in astrophysics. One of the primary challenges has been the necessity for prolonged…

High Energy Astrophysical Phenomena · Physics 2025-10-23 P. Peñil , A. Domínguez , S. Buson , M. Ajello , S. Adhikari , A. Rico

The brightest blazars detected by the Fermi Gamma-ray Space Telescope Large Area Telescope (Fermi/LAT) show significant breaks in their spectra at a few GeV. The sharpness and the position of the breaks can be well reproduced by absorption…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-08 Juri Poutanen , Boris E. Stern

Understanding the high-energy emission processes and variability patterns are two of the most challenging research problems associated with relativistic jets. In particular, the long-term (months-to-years) flux variability at very high…

High Energy Astrophysical Phenomena · Physics 2024-01-23 Vaidehi S. Paliya

During its first six years of operation, the Fermi Large Area Telescope (LAT) has detected >30 MeV gamma-ray emission from more than 40 solar flares, nearly a factor of 10 more than those detected by EGRET. These include detections of…

High Energy Astrophysical Phenomena · Physics 2019-08-14 N. Omodei , V. Petrosian , W. Liu , F. Rubio da Costa , Q. Chen , M. Pesce-Rollins , E. Grove , F. Longo

We present the result of a search of the Milagro sky map for spatial correlations with sources from a subset of the recent Fermi Bright Source List (BSL). The BSL consists of the 205 most significant sources detected above 100 MeV by the…

A list of 205 gamma-ray strong objects was reported recently as a result of a 3-month integration with the Large Area Telescope on board the Fermi Gamma-Ray Space Telescope. We attempted identification of these objects, cross-correlating…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Y. Y. Kovalev

The Fermi-LAT has detected more than 3000 sources in the GeV $\gamma$-ray regime. The majority are extra-galactic and these sources are dominated by blazars. However, $\sim28$ per cent of the sources in Fermi 3LAC are listed as blazar…

High Energy Astrophysical Phenomena · Physics 2017-02-01 L. Klindt , B. van Soelen , P. J. Meintjes , P. Väisänen

Before the launch of the Fermi Gamma-ray Space Telescope there were only a handful of gamma-ray bursts (GRBs) detected at high energies (above 100 MeV), while several different suggestions have been made for possible high-energy emission…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Jonathan Granot

This paper reports the results from three targeted searches of Milagro TeV sky maps: two extragalactic point source lists and one pulsar source list. The first extragalactic candidate list consists of 709 candidates selected from the…

Very high energy (VHE, energy $E \gtrsim 100$\,GeV) \gamma-rays from cosmological sources are attenuated due to the interaction with photons of the extragalactic background light (EBL) in the ultraviolet to infrared wavelength band. The…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-05 Manuel Meyer , Martin Raue , Daniel Mazin , Dieter Horns

The F -GAMMA program is a coordinated effort of several observing facilities to understand the AGN/blazar phenomenon via a multi-frequency monitoring approach, especially in the era of Fermi-GST. Some 60 prominent sources are monitored…

Cosmology and Nongalactic Astrophysics · Physics 2010-07-01 E. Angelakis , L. Fuhrmann , I. Nestoras , J. A. Zensus , N. Marchili , V. Pavlidou , T. P. Krichbaum

The third Fermi Large Area Telescope (LAT) $\gamma$-ray source catalog (3FGL) contains over 1000 objects for which there is no known counterpart at other wavelengths. The physical origin of the $\gamma$-ray emission of those objects is…

High Energy Astrophysical Phenomena · Physics 2017-04-12 F. K. Schinzel , L. Petrov , G. B. Taylor , P. G. Edwards

We report the Fermi-LAT discovery of high-energy (MeV/GeV) gamma-ray emission positionally consistent with the center of the radio galaxy M87, at a source significance of over 10 sigma in ten-months of all-sky survey data. Following the…

High Energy Astrophysical Phenomena · Physics 2009-12-04 The Fermi LAT Collaboration , A. A. Abdo , D. E. Harris , F. Massaro , L. Stawarz

Gamma rays from extragalactic sources are attenuated by pair-production interactions with diffuse photons of the extragalactic background light (EBL). Gamma-ray bursts (GRBs) are a source of high-redshift photons above 10 GeV, and could be…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Rudy C. Gilmore , Francisco Prada , Joel R. Primack

Although the Fermi mission has increased our knowledge of gamma-ray AGN, many questions remain, such as the site of gamma-ray production, the emission mechanism, and the factors that govern the strength of the emission. Using data from a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 E. Nieppola , M. Tornikoski , E. Valtaoja , J. León-Tavares , T. Hovatta , A. Lähteenmäki , J. Tammi

Fast radio bursts (FRBs) are one of the most exciting new mysteries of astrophysics. Their origin is still unknown, but recent observations seems to link them to Soft Gamma Repeaters and, in particular, to magnetar giant flares (MGFs). The…

High Energy Astrophysical Phenomena · Physics 2021-09-23 Giacomo Principe , Nicola Omodei , Niccolò Di Lalla , Leonardo Di Venere , Francesco Longo

The Fermi Gamma-ray Space Telescope regularly surveys the entire sky in the energy range between 0.3 and 100 GeV with an homogeneous coverage. This makes Fermi a very useful guide for ground-based Cherenkov-telescope arrays like VERITAS,…

High Energy Astrophysical Phenomena · Physics 2015-05-30 M. Errando , M. Orr , E. Kara

The Large Area Telescope (LAT) on board the Fermi satellite has detected ~120 pulsars above 100 MeV. While most gamma-ray pulsars have spectra that are well modeled by a power law with an exponential cut-off at around a few GeV, some show…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Pablo M. Saz Parkinson
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