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Related papers: Fermi observations of TeV AGN

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The Fermi-LAT has observed new gamma-ray flares from the blazar B0218+357 during July 2014. While no significant change in the gamma-ray spectrum has been previously observed through the flaring phase in late-2012, during this recent high…

High Energy Astrophysical Phenomena · Physics 2015-02-12 S. Buson , C. C. Cheung , S. Larsson , J. D. Scargle

The first Gamma-Ray Burst (GRB) catalog presented by the Fermi-Large Area Telescope (LAT) collaboration includes 28 GRBs, detected above 100 MeV over the first three years since the launch of the Fermi mission. However, more than 100 GRBs…

High Energy Astrophysical Phenomena · Physics 2015-09-07 Elisabetta Bissaldi , Tristano Di Girolamo , Francesco Longo , Piero Vallania , Carlo Vigorito

We report on TeV gamma-ray observations of the blazar Mrk 421 (redshift of 0.031) with the VERITAS observatory and the Whipple 10m Cherenkov telescope. The excellent sensitivity of VERITAS allowed us to sample the TeV gamma-ray fluxes and…

Gamma rays at rest frame energies as high as 90 GeV have been reported from gamma-ray bursts (GRBs) by the Fermi Large Area Telescope (LAT). There is considerable hope that a confirmed GRB detection will be possible with the upcoming…

High Energy Astrophysical Phenomena · Physics 2015-06-03 Rudy C. Gilmore , Aurelien Bouvier , Valerie Connaughton , Adam Goldstein , Nepomuk Otte , Joel R. Primack , David A. Williams

Although not designed primarily as a polarimeter, the \textit{Fermi}-Large Area Telescope (LAT) has the potential to detect high degrees of linear polarization from some of the brightest gamma-ray sources. To achieve the needed accuracy in…

Instrumentation and Methods for Astrophysics · Physics 2019-08-14 Matteo Giomi , Rolf Bühler , Carmelo Sgrò , Francesco Longo , William Atwood

The Large Area Telescope on the Fermi gamma-ray Space Telescope (FGST, ex-GLAST) provides unprecedented sensitivity for all-sky monitoring of gamma-ray activity. It is an adequate telescope to detect transient sources, since the observatory…

High Energy Astrophysical Phenomena · Physics 2010-08-25 Sylvain Chaty

The Fermi Large Area Telescope (LAT) has an instantaneous field of view covering $\sim 1/5$ of the sky and completes a survey of the full sky every ~3 hours. It provides a continuous, all-sky survey of high-energy gamma-rays, enabling…

High Energy Astrophysical Phenomena · Physics 2016-06-01 LAT collaboration

The Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope is a pair-conversion telescope designed to detect photons with energies from 20 MeV to > 300 GeV. The pre-launch response functions of the LAT were determined through…

High Energy Astrophysical Phenomena · Physics 2016-03-23 LAT Collaboration

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

In the first 3.5 years of operations the Fermi LAT detected several sources with daily fluxes brighter than F(E>100MeV) > 10^{-6} ph/cm^2/s, the threshold set by the Fermi Collaboration for issuing an Astronomer Telegram. We focus the…

High Energy Astrophysical Phenomena · Physics 2013-03-13 S. Buson , D. Bastieri , F. D'Ammando , G. Tosti

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

In many theoretical models of gamma-ray bursts (GRBs) and their afterglows, the emission of photons above 100 GeV is predicted. The Large Area Telescope (LAT) on-board the Fermi Gamma-ray Space Telescope has detected delayed, high-energy…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Taylor Aune

AIMS. We are studying an unbiased sample of 42 nearby (z < 0.2) BL Lacertae objects with a multi-wavelength approach. The results of VLBI observations were presented in the first paper of this series. In this paper, we study the…

High Energy Astrophysical Phenomena · Physics 2018-11-08 F. D'Ammando , M. Giroletti , S. Rainò

Radio galaxies are relatively faint at $\gamma$-ray energies, where they make up only 1-2% of all AGN detected by Fermi-LAT. However, they offer a unique perspective to study the intrinsic properties of AGN jets. For this reason, the…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Roberto Angioni , Florian Rösch , Eduardo Ros , Matthias Kadler , Roopesh Ojha , Cornelia Müller , Robert Schulz

Fermi has provided the largest sample of gamma-ray selected blazars to date. In this work we use a uniformly selected set of 211 BL Lacertae (BL Lac) objects detected by it Fermi during its first year of operation. We have obtained redshift…

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

We are compiling a new list of gamma-ray jetted active galactic nuclei (AGN), starting from the fourth catalog of point sources of the Fermi Large Area Telescope (LAT). Our aim is to prepare a list of jetted AGN with known redshifts and…

High Energy Astrophysical Phenomena · Physics 2021-10-06 L. Foschini , M. L. Lister , S. Antón , M. Berton , S. Ciroi , M. J. M. Marchã , M. Tornikoski , E. Järvelä , P. Romano , S. Vercellone , E. Dalla Bontà

Can we learn about New Physics with astronomical and astro-particle data? Since its launch in 2008, the Large Area Telescope, onboard of the Fermi Gamma-ray Space Telescope, has detected the largest amount of gamma rays in the 20 MeV - 300…

High Energy Astrophysical Phenomena · Physics 2022-03-02 A. Morselli , E. Nuss , G. Zaharijas

We present gamma-ray observations with the LAT on board the Fermi Gamma-Ray Telescope of the nearby radio galaxy Centaurus~A. The previous EGRET detection is confirmed, and the localization is improved using data from the first 10 months of…

High Energy Astrophysical Phenomena · Physics 2015-05-19 Fermi Collaboration , A. Falcone , H. Hase , C. Pagoni , C. Ploetz

The Fermi Large Area Telescope (LAT) has provided the measurement of the high energy cosmic ray electrons plus positrons (CRE) spectrum with unprecedented accuracy form 20 GeV to 1 TeV. Recently this range has been extended down to ~ 7 GeV.…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Giuseppe Di Bernardo , Daniele Gaggero , Dario Grasso
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