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Related papers: Variable gamma-ray sky at 1 GeV

200 papers

We perform a blind search for the variability of the gamma-ray sky in the energy range E>1 GeV using 308 weeks of the Fermi-LAT data. We use the technique based on the comparison of the weekly photon counts and exposures in sky pixels by…

High Energy Astrophysical Phenomena · Physics 2015-12-22 M. S. Pshirkov , G. I. Rubtsov

The Fermi All-sky Variability Analysis (FAVA) provides a photometric alternative for identifying week-long gamma-ray flares across the entire sky while being independent of any diffuse Galactic or isotropic emission model. We reviewed 779…

High Energy Astrophysical Phenomena · Physics 2024-02-29 Scott D. Joffre , Núria Torres-Albà , Marco Ajello , Daniel Kocevski , Rolf Buehler

In this paper we present the Fermi All-sky Variability Analysis (FAVA), a tool to systematically study the variability of the gamma-ray sky measured by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope. For each…

High Energy Astrophysical Phenomena · Physics 2013-07-15 LAT Collaboration

A systematic search for cyclical sources of gamma-ray emission on the period range from days to years in the Fermi-LAT sky is performed. Looking for cyclical emission, the sky is binned into equal-area pixels and the generalised…

High Energy Astrophysical Phenomena · Physics 2017-07-20 D. A. Prokhorov , A. Moraghan

High-energy gamma-ray emission from the Galactic plane above ~100 MeV is composed of three main contributions: diffuse emission from cosmic ray interactions in the interstellar medium, emission from extended sources, such as supernova…

High Energy Astrophysical Phenomena · Physics 2015-06-05 A. Neronov , D. Malyshev , M. Chernyakova , A. Lutovinov

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

We present the second catalog of flaring gamma-ray sources (2FAV) detected with the Fermi All-sky Variability Analysis (FAVA), a tool that blindly searches for transients over the entire sky observed by the Large Area Telescope (LAT) on…

High Energy Astrophysical Phenomena · Physics 2017-09-13 S. Abdollahi , M. Ackermann , M. Ajello , A. Albert , L. Baldini , J. Ballet , G. Barbiellini , D. Bastieri , J. Becerra Gonzalez , R. Bellazzini , E. Bissaldi , R. D. Blandford , E. D. Bloom , R. Bonino , E. Bottacini , J. Bregeon , P. Bruel , R. Buehler , S. Buson , R. A. Cameron , M. Caragiulo , P. A. Caraveo , E. Cavazzuti , C. Cecchi , A. Chekhtman , C. C. Cheung , G. Chiaro , S. Ciprini , J. Conrad , D. Costantin , F. Costanza , S. Cutini , F. D'Ammando , F. de Palma , A. Desai , R. Desiante , S. W. Digel , N. Di Lalla , M. Di Mauro , L. Di Venere , B. Donaggio , P. S. Drell , C. Favuzzi , S. J. Fegan , E. C. Ferrara , W. B. Focke , A. Franckowiak , Y. Fukazawa , S. Funk , P. Fusco , F. Gargano , D. Gasparrini , N. Giglietto , M. Giomi , F. Giordano , M. Giroletti , T. Glanzman , D. Green , I. A. Grenier , J. E. Grove , L. Guillemot , S. Guiriec , E. Hays , D. Horan , T. Jogler , G. Jóhannesson , A. S. Johnson , D. Kocevski , M. Kuss , G. La Mura , S. Larsson , L. Latronico , J. Li , F. Longo , F. Loparco , M. N. Lovellette , P. Lubrano , J. D. Magill , S. Maldera , A. Manfreda , M. Mayer , M. N. Mazziotta , P. F. Michelson , W. Mitthumsiri , T. Mizuno , M. E. Monzani , A. Morselli , I. V. Moskalenko , M. Negro , E. Nuss , T. Ohsugi , N. Omodei , M. Orienti , E. Orlando , V. S. Paliya , D. Paneque , J. S. Perkins , M. Persic , M. Pesce-Rollins , V. Petrosian , F. Piron , T. A. Porter , G. Principe , S. Rainò , R. Rando , M. Razzano , S. Razzaque , A. Reimer , O. Reimer , C. Sgrò , D. Simone , E. J. Siskind , F. Spada , G. Spandre , P. Spinelli , L. Stawarz , D. J. Suson , M. Takahashi , K. Tanaka , J. B. Thayer , D. J. Thompson , D. F. Torres , E. Torresi , G. Tosti , E. Troja , G. Vianello , K. S. Wood

We conducted an analysis of gamma-ray variability in a large sample of jetted active galactic nuclei (AGNs) by utilizing archival Fermi-LAT light curves and applying damped random walk modeling to obtain variability amplitude. Our primary…

High Energy Astrophysical Phenomena · Physics 2026-05-21 Yongyun Chen , Qiusheng Gu , Junhui Fan , Dingrong Xiong , Xiaoling Yu , Xiaogu Zhong , Xiaotong Guo , Nan Ding

We present a comprehensive analysis of the 17-year Fermi-LAT observational data of Mrk 421 to investigate the spectral variations in the $\gamma$-ray bands. The light curve of the source in the 0.1--1000 GeV band with a 14-day time bin…

High Energy Astrophysical Phenomena · Physics 2026-03-18 Rui-Qi Huang , Xin-Ke Hu , Yu-Wei Yu , Ji-Shun Lian , Jin Zhang

High-redshift blazars are one of the most powerful monsters in the universe and $\gamma$-ray variability carries crucial information of their relativistic jets. In this work we present results of the first systematical temporal analysis of…

High Energy Astrophysical Phenomena · Physics 2018-02-14 Shang Li , Zi-Qing Xia , Yun-Feng Liang , Neng-Hui Liao , Yi-Zhong Fan

Variable \gama-ray emission from blazars, one of the most powerful classes of astronomical sources featuring relativistic jets, is a widely discussed topic. In this work, we present the results of a variability study of a sample of 20…

High Energy Astrophysical Phenomena · Physics 2021-09-22 Jaroslaw Duda , Gopal Bhatta

Active Galactic Nuclei (AGN) sources feature supermassive black holes that launch relativistic plasma jets. They are key $\gamma$-ray sources providing a unique laboratory for studying extreme particle acceleration and plasma physics.…

High Energy Astrophysical Phenomena · Physics 2026-02-03 Luana Passos-Reis , Elisabete M. de Gouveia Dal Pino , Tarek Hassan , Santiago Pita , Alberto Domínguez

We search for gamma-ray emission from 114 Galactic high mass X-ray binaries, including 4 well studied catalogued sources, in 12.5 years of Fermi-LAT data in conjunction with the 10-year point source catalogue. Where a gamma-ray excess…

High Energy Astrophysical Phenomena · Physics 2022-03-02 Max Harvey , Cameron B. Rulten , Paula M. Chadwick

We present results of variability study of a sample of 20 powerful blazars using Fermi/LAT (0.1--300 GeV) observations. We studied decade-long observations applying various analysis tools such as flux distribution, symmetry analysis, and…

High Energy Astrophysical Phenomena · Physics 2021-07-27 Gopal Bhatta , Niraj Dhital

This is the first report of Fermi Gamma-ray Space Telescope observations of the quasar 3C 454.3, which has been undergoing pronounced long-term outbursts since 2000. The data from the Large Area Telescope (LAT), covering 2008 July 7 -…

High Energy Astrophysical Phenomena · Physics 2012-08-27 LAT Collaboration , A. A. Abdo

Over the past 16 years, the Fermi Large Area Telescope (LAT) has significantly advanced our view of the GeV gamma-ray sky, yet several key questions remain - such as the composition of the isotropic gamma-ray background, the origin of the…

High Energy Astrophysical Phenomena · Physics 2025-05-07 Christopher Eckner , Noemi Anau Montel , Florian List , Francesca Calore , Christoph Weniger

Blazars, a subset of powerful active galactic nuclei, feature relativistic jets that shine in a broadband electromagnetic radiation, e. g. from radio to TeV emission. Here I present the results of the studies that explore gamma-ray and…

High Energy Astrophysical Phenomena · Physics 2022-10-18 Gopal Bhatta

The recent detection of gamma-ray emission from four radio-loud narrow-line Seyfert 1 galaxies suggests that the engine driving the AGN activity of these objects share some similarities with that of blazars, namely the presence of a…

High Energy Astrophysical Phenomena · Physics 2015-05-20 G. Calderone , L. Foschini , G. Ghisellini , M. Colpi , L. Maraschi , F. Tavecchio , R. Decarli , G. Tagliaferri

Blazars are known to exhibit variability across a broad range of timescales. This behavior can include periodicity in their $\gamma$-ray emission, whose clear detection remains an ongoing challenge, partly due to the inherent stochasticity…

High Energy Astrophysical Phenomena · Physics 2025-07-08 P. Peñil , M. Ajello , S. Buson , A. Domínguez , J. R. Westernacher-Schneider , A. Rico , S. Adhikari , J. Zrake
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