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Related papers: Revisiting variable gamma-ray sky at 1 GeV with 6 …

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We search for the long-term variability of the \gamma-ray sky in the energy range E > 1 GeV with 168 weeks of Fermi-LAT data. We perform a full sky blind search for regions with variable flux looking for deviations from uniformity. We bin…

High Energy Astrophysical Phenomena · Physics 2015-06-03 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

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

The Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope routinely detects the highly dust-absorbed, reddened, and MeV-peaked flat spectrum radio quasar PKS 1830-211 (z=2.507). Its apparent isotropic gamma-ray luminosity…

High Energy Astrophysical Phenomena · Physics 2015-06-23 The Fermi LAT Collaboration , A. A. Abdo , M. Ackermann , M. Ajello , A. Allafort , M. A. Amin , L. Baldini , G. Barbiellini , D. Bastieri , K. Bechtol , R. Bellazzini , R. D. Blandford , E. Bonamente , A. W. Borgland , J. Bregeon , M. Brigida , R. Buehler , D. Bulmash , S. Buson , G. A. Caliandro , R. A. Cameron , P. A. Caraveo , E. Cavazzuti , C. Cecchi , E. Charles , C. C. Cheung , J. Chiang , G. Chiaro , S. Ciprini , R. Claus , J. Cohen-Tanugi , J. Conrad , R. H. D. Corbet , S. Cutini , F. D'Ammando , A. de Angelis , F. de Palma , C. D. Dermer , P. S. Drell , A. Drlica-Wagner , C. Favuzzi , J. Finke , W. B. Focke , Y. Fukazawa , P. Fusco , F. Gargano , D. Gasparrini , N. Gehrels , N. Giglietto , F. Giordano , M. Giroletti , T. Glanzman , I. A. Grenier , J. E. Grove , S. Guiriec , D. Hadasch , M. Hayashida , E. Hays , R. E. Hughes , Y. Inoue , M. S. Jackson , T. Jogler , G. Jòhannesson , A. S. Johnson , T. Kamae , J. Knödlseder , M. Kuss , J. Lande , S. Larsson , L. Latronico , F. Longo , F. Loparco , B. Lott , M. N. Lovellette , P. Lubrano , G. M. Madejski , M. N. Mazziotta , J. Mehault , P. F. Michelson , T. Mizuno , M. E. Monzani , A. Morselli , I. V. Moskalenko , S. Murgia , R. Nemmen , E. Nuss , M. Ohno , T. Ohsugi , D. Paneque , J. S. Perkins , M. Pesce-Rollins , F. Piron , G. Pivato , T. A. Porter , S. Rainò , R. Rando , M. Razzano , A. Reimer , O. Reimer , L. C. Reyes , S. Ritz , C. Romoli , M. Roth , P. M. Saz Parkinson , C. Sgrò , E. J. Siskind , G. Spandre , P. Spinelli , H. Takahashi , Y. Takeuchi , T. Tanaka , J. G. Thayer , J. B. Thayer , D. J. Thompson , L. Tibaldo , M. Tinivella , D. F. Torres , G. Tosti , E. Troja , V. Tronconi , T. L. Usher , J. Vandenbroucke , V. Vasileiou , G. Vianello , V. Vitale , A. P. Waite , M. Werner , B. L. Winer , K. S. Wood

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

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

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

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

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

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 3 years of the Fermi Gamma-ray Space Telescope mission. This catalog complements the Second…

High Energy Astrophysical Phenomena · Physics 2013-04-16 David Paneque , Jean Ballet , Toby Burnett , Seth Digel , Pascal Fortin , Juergen Knoedlseder

The GeV observations by Fermi-LAT give us the opportunity to characterize the high-energy emission (100 MeV - 300 GeV) variability properties of the BL Lac object S5 0716+714. In this study, we performed flux and spectral analysis of more…

High Energy Astrophysical Phenomena · Physics 2015-06-15 B. Rani , T. P. Krichbaum , B. Lott , L. Fuhrmann , J. A. Zensus

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

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

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

Here we report on the detailed analysis of the gamma-ray light curve of a luminous blazar PKS1510-089 observed in the GeV range with the Large Area Telescope (LAT) onboard the Fermi satellite during the period 2011 September -- December. By…

High Energy Astrophysical Phenomena · Physics 2015-06-12 S. Saito , L. Stawarz , Y. T. Tanaka , T. Takahashi , G. Madejski , F. D'Ammando

We report the detection of two new gamma-ray sources in the Fermi-LAT sky (Pass 8) at energies higher than 20 GeV, and confirmed at lower energies, using a source detection tool based on the Minimum Spanning Tree algorithm. One of these…

High Energy Astrophysical Phenomena · Physics 2017-01-25 R. Campana , A. Maselli , E. Bernieri , E. Massaro

This paper presents light curves and the first systematic characterization of variability of the 106 objects in the Fermi Large Area Telescope (LAT) Bright AGN Sample (LBAS). Weekly light curves obtained during the first 11 months of survey…

High Energy Astrophysical Phenomena · Physics 2015-05-18 A. A. Abdo

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

We present a catalog of high-energy gamma-ray sources detected by the Large Area Telescope (LAT), the primary science instrument on the Fermi Gamma-ray Space Telescope (Fermi), during the first 11 months of the science phase of the mission,…

High Energy Astrophysical Phenomena · Physics 2015-05-18 LAT Collaboration

We present the results of our follow-up observation program of gamma-ray sources detected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope. 26 blazars and 39 sources unidentified at other wavelengths were…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Mai Fujiwara , Yoshiki Matsuoka , Nobuyuki Ienaka
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