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Related papers: Hunting for New Gamma-ray Binaries - Technique Dev…

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We present a method enabling the creation of constant-uncertainty/constant-significance light curves with the data of the Fermi-Large Area Telescope (LAT). The adaptive-binning method enables more information to be encapsulated within the…

High Energy Astrophysical Phenomena · Physics 2015-06-03 B. Lott , L. Escande , S. Larsson , J. Ballet

After initial claims and a long hiatus, it is now established that several binary stars emit high (0.1-100 GeV) and very high energy (>100 GeV) gamma rays. A new class has emerged called 'gamma-ray binaries', since most of their radiated…

High Energy Astrophysical Phenomena · Physics 2013-09-06 Guillaume Dubus

The second Fermi-LAT source catalog (2FGL) is the deepest all-sky survey available in the gamma-ray band. It contains 1873 sources, of which 576 remain unassociated. Machine-learning algorithms can be trained on the gamma-ray properties of…

High Energy Astrophysical Phenomena · Physics 2014-01-29 M. Doert , M. Errando

X-ray and gamma-ray binaries are systems consisting of a compact object and normally a non-degenerate companion star. Most of these sources have been shown to emit radiation in a broad frequency range, from radio up to X-rays and sometimes…

High Energy Astrophysical Phenomena · Physics 2022-09-22 E. Molina , A. López-Oramas , D. Hadasch , J. Hoang

We describe an ongoing optical spectrophotometric monitoring program of a sample of Fermi/LAT bright sources showing prominent and variable {\gamma}-ray emission, with the 2.1m telescope at Observatorio Astrof\'isico Guillermo Haro (OAGH)…

High Energy Astrophysical Phenomena · Physics 2013-04-19 V. Patiño-Álvarez , V. Chavushyan , J. León-Tavares , J. R. Valdés , A. Carramiñana , L. Carrasco , J. Torrealba

Non-thermal variable emission from radio to very-high energy gamma rays (VHE; >100 GeV) are the prime characteristics of gamma-ray binaries. The underlying physical processes leading to the observed VHE emission are not well understood, as…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Gernot Maier

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

We discuss Fermi observations of gamma-ray loud binaries. We show that within hadronic model of activity of LSI +61 303, detection of cut-off in the GeV spectrum constrains maximal energy of the primary protons. In this way, the GeV…

High Energy Astrophysical Phenomena · Physics 2009-12-22 M. Chernyakova , A. Neronov , M. Ribordy

Blazars are a small fraction of all extragalactic sources but, unlike other objects, they are strong emitters across the entire electromagnetic spectrum. Recent data in the microwave region of the electromagnetic spectrum have become…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-24 D. Gasparrini , E. Cavazzuti , P. Giommi , C. Pittori , S. Colafrancesco , Fermi-LAT collaboration

The nature of most of the ~300 high-energy gamma-ray sources discovered by the EGRET instrument aboard the Gamma-ray Observatory (GRO) between 1991 and 1999 is one of the greatest enigmas in high-energy astrophysics. While about half of the…

High Energy Astrophysical Phenomena · Physics 2009-02-05 R. P. Mignani

Using public \fermi LAT and \swift BAT observations, we constructed the first sample of blazars selected at both hard X-rays and gamma-rays. Studying its spectral properties, we find a luminosity dependence of the spectral slopes at both…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-22 R. M. Sambruna , D. Donato , M. Ajello , L. Maraschi , the GSFC BAT Team

Classification of gamma-ray bursts (GRBs) has been a long-standing puzzle in high-energy astrophysics. Recent observations challenge the traditional short vs. long viewpoint, where long GRBs are thought to originate from the collapse of…

High Energy Astrophysical Phenomena · Physics 2024-09-02 Dimple , K. Misra , K. G. Arun

The Large Area Telescope (LAT) on the Fermi satellite is the first gamma-ray instrument to discover pulsars directly via their gamma-ray emission. Roughly one third of the 117 gamma-ray pulsars detected by the LAT in its first three years…

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

We present a systematic study of gamma-ray blazar candidates based on a sample of 40 objects taken from the WIBR catalogue. By using a likelihood analysis, 26 of the 40 sources showed significant gamma-ray signatures $\geq3\sigma$. Using…

High Energy Astrophysical Phenomena · Physics 2021-07-14 Blessing Musiimenta , Bruno Sversut Arsioli , Edward Jurua , Tom Mutabazi

Stellar sources of gamma rays are one of the front lines in modern astrophysics whose understanding can benefit from observational tools not originally designed for their study. We take advantage of the high precision photometric…

High Energy Astrophysical Phenomena · Physics 2022-06-08 Enrique Mestre , Estrella Sánchez-Ayaso , Pedro L. Luque-Escamilla , Josep Martí , Josep M. Paredes , Daniel del Ser , Jorge Núñez

In our previous work in Xiao et al. (2019), we suggested that 6 superluminal sources could be gamma-ray candidates, and in fact 5 of them have been confirmed in the fourth Fermi-LAT source catalogue (4FGL). In this work, based on the 4FGL,…

High Energy Astrophysical Phenomena · Physics 2020-07-15 Hubing Xiao , Junhui Fan , Riccardo Rando , Jingtian Zhu , Liangjun Hu

In three years of observations since the beginning of nominal science operations in August 2008, the Large Area Telescope (LAT) on board the Fermi Gamma Ray Space Telescope has observed high-energy (>20 MeV) \gamma-ray emission from 35…

High Energy Astrophysical Phenomena · Physics 2015-06-15 LAT Collaboration

In the first two years since the launch of the Fermi Observatory, the Gamma-ray Burst Monitor (GBM) has detected over 500 Gamma-Ray Bursts (GRBs), of which 18 were confidently detected by the Large Area Telescope (LAT) above 100 MeV.…

High Energy Astrophysical Phenomena · Physics 2022-03-02 Elisabetta Bissaldi

The Fermi Large Area Telescope (LAT) light curve repository (LCR) is a publicly available, continually updated library of gamma-ray light curves of variable Fermi-LAT sources generated over multiple timescales. The Fermi-LAT LCR aims to…

High Energy Astrophysical Phenomena · Physics 2023-03-29 S. Abdollahi , M. Ajello , L. Baldini , J. Ballet , D. Bastieri , J. Becerra Gonzalez , R. Bellazzini , A. Berretta , E. Bissaldi , R. Bonino , A. Brill , P. Bruel , E. Burns , S. Buson , A. Cameron , R. Caputo , P. A. Caraveo , N. Cibrario , S. Ciprini , P. Cristarella Orestano , M. Crnogorcevic , S. Cutini , F. D'Ammando , S. De Gaetano , S. W. Digel , N. Di Lalla , L. Di Venere , A. Domínguez , V. Fallah Ramazani , S. J. Fegan , E. C. Ferrara , A. Fiori , H. Fleischhack , A. Franckowiak , Y. Fukazawa , P. Fusco , V. Gammaldi , F. Gargano , S. Garrappa , C. Gasbarra , D. Gasparrini , N. Giglietto , F. Giordano , M. Giroletti , D. Green , I. A. Grenier , S. Guiriec , M. Gustafsson , E. Hays , D. Horan , X. Hou , G. Jóhannesson , M. Kerr , D. Kocevski , M. Kuss , L. Latronico , J. Li , I. Liodakis , F. Longo , F. Loparco , L. Lorusso , B. Lott , M. N. Lovellette , P. Lubrano , S. Maldera , A. Manfreda , G. Mart\'-Devesa , M. N. Mazziotta , I. Mereu , M. Meyer , P. F. Michelson , T. Mizuno , M. E. Monzani , A. Morselli , I. V. Moskalenko , M. Negro , N. Omodei , E. Orlando , J. F. Ormes , D. Paneque , G. Panzarini , J. S. Perkins , M. Persic , M. Pesce-Rollins , R. Pillera , T. A. Porter , G. Principe , J. L. Racusin , S. Rainò , R. Rando , B. Rani , M. Razzano , S. Razzaque , A. Reimer , O. Reimer , M. Sánchez-Conde , P. M. Saz Parkinson , Jeff Scargle , L. Scotton , D. Serini , C. Sgrò , E. J. Siskind , G. Spandre , P. Spinelli , D. J. Suson , H. Tajima , D. J. Thompson , D. F. Torres , J. Valverde , T. Venters , Z. Wadiasingh , S. Wagner , K. Wood

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