Related papers: On the gamma-ray emission from 3C 120

Gamma-ray flaring activity of NGC 1275 in 2016-2017 measured by MAGIC

We report on the detection of flaring activity from the Fanaroff-Riley I radio galaxy NGC 1275 in very-high-energy (VHE, E $>$ 100 GeV) gamma rays with the MAGIC telescopes. Observations were performed between 2016 September and 2017…

High Energy Astrophysical Phenomena · Physics 2018-09-26 MAGIC collaboration , S. Ansoldi , L. A. Antonelli , C. Arcaro , D. Baack , A. Babić , B. Banerjee , P. Bangale , U. Barres de Almeida , J. A. Barrio , J. Becerra González , W. Bednarek , E. Bernardini , R. Ch. Berse , A. Berti , W. Bhattacharyya , C. Bigongiari , A. Biland , O. Blanch , G. Bonnoli , R. Carosi , G. Ceribella , A. Chatterjee , S. M. Colak , P. Colin , E. Colombo , J. L. Contreras , J. Cortina , S. Covino , P. Cumani , V. D'Elia , P. Da Vela , F. Dazzi , A. De Angelis , B. De Lotto , M. Delfino , J. Delgado , F. Di Pierro , A. Domínguez , D. Dominis Prester , D. Dorner , M. Doro , S. Einecke , D. Elsaesser , V. Fallah Ramazani , A. Fattorini , A. Fernández-Barral , G. Ferrara , D. Fidalgo , L. Foffano , M. V. Fonseca , L. Font , C. Fruck , D. Galindo , S. Gallozzi , R. J. García López , M. Garczarczyk , M. Gaug , P. Giammaria , N. Godinović , D. Gora , D. Guberman , D. Hadasch , A. Hahn , T. Hassan , M. Hayashida , J. Herrera , J. Hoang , J. Hose , D. Hrupec , K. Ishio , Y. Konno , H. Kubo , J. Kushida , A. Lamastra , D. Lelas , F. Leone , E. Lindfors , S. Lombardi , F. Longo , M. López , C. Maggio , P. Majumdar , M. Makariev , G. Maneva , M. Manganaro , K. Mannheim , L. Maraschi , M. Mariotti , M. Martínez , S. Masuda , D. Mazin , K. Mielke , M. Minev , J. M. Miranda , R. Mirzoyan , A. Moralejo , V. Moreno , E. Moretti , T. Nagayoshi , V. Neustroev , A. Niedzwiecki , M. Nievas Rosillo , C. Nigro , K. Nilsson , D. Ninci , K. Nishijima , K. Noda , L. Nogués , S. Paiano , J. Palacio , D. Paneque , R. Paoletti , J. M. Paredes , G. Pedaletti , P. Peñil , M. Peresano , M. Persic , K. Pfrang , P. G. Prada Moroni , E. Prandini , I. Puljak , J. R. Garcia , I. Reichardt , W. Rhode , M. Ribó , J. Rico , C. Righi , A. Rugliancich , L. Saha , T. Saito , K. Satalecka , T. Schweizer , J. Sitarek , I. Šnidarić , D. Sobczynska , A. Stamerra , M. Strzys , T. Surić , M. Takahashi , F. Tavecchio , P. Temnikov , T. Terzić , M. Teshima , N. Torres-Albà , S. Tsujimoto , G. Vanzo , M. Vazquez Acosta , I. Vovk , J. E. Ward , M. Will , D. Zarić , D. Glawion , L. O. Takalo , J. Jormanainen

Exploring the central sub-pc region of the \gamma-ray bright radio galaxy 3C 84 with the VLBA at 43 GHz in the period of 2002-2008

Following the discovery of a new radio component right before the GeV \gamma-ray detection since 2008 August by Fermi Gamma-ray Space Telescope, we present a detailed study of the kinematics and lightcurve on the central sub-pc scale of 3C…

High Energy Astrophysical Phenomena · Physics 2011-12-06 Kenta Suzuki , Hiroshi Nagai , Motoki Kino , Jun Kataoka , Keiichi Asada , Akihiro Doi , Makoto Inoue , Monica Orienti , Gabriele Giovannini , Marcello Giroletti , Anne Lähteenmäki , Merja Tornikoski , Jonathan León-Tavares , Uwe Bach , Seiji Kameno , Hideyuki Kobayashi

Search for variable gamma-ray emission from the Galactic plane in the Fermi data

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

Highlights from Fermi GRB observations

The Fermi Gamma-Ray Space Telescope has more than doubled the number of Gamma-Ray Bursts (GRBs) detected above 100 MeV within its first year of operation. Thanks to the very wide energy range covered by Fermi's Gamma-ray Burst Monitor (GBM;…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Jonathan Granot

The $\gamma$-ray spectrum of the core of Centaurus A as observed with H.E.S.S. and Fermi-LAT

Centaurus A (Cen A) is the nearest radio galaxy discovered as a very-high-energy (VHE; 100 GeV-100 TeV) $\gamma$-ray source by the High Energy Stereoscopic System (H.E.S.S.). It is a faint VHE $\gamma$-ray emitter, though its VHE flux…

High Energy Astrophysical Phenomena · Physics 2018-11-14 H. E. S. S. Collaboration , H. Abdalla , A. Abramowski , F. Aharonian , F. Ait Benkhali , E. O. Angüner , M. Arakawa , C. Armand , M. Arrieta , M. Backes , A. Balzer , M. Barnard , Y. Becherini , J. Becker Tjus , D. Berge , S. Bernhard , K. Bernlöhr , R. Blackwell , M. Böttcher , C. Boisson , J. Bolmont , S. Bonnefoy , P. Bordas , J. Bregeon , F. Brun , P. Brun , M. Bryan , M. Büchele , T. Bulik , M. Capasso , S. Caroff , A. Carosi , S. Casanova , M. Cerruti , N. Chakraborty , R. C. G. Chaves , A. Chen , J. Chevalier , S. Colafrancesco , B. Condon , J. Conrad , I. D. Davids , J. Decock , C. Deil , J. Devin , P. deWilt , L. Dirson , A. Djannati-Ataï , A. Donath , L. O'C. Drury , J. Dyks , T. Edwards , K. Egberts , G. Emery , J. -P. Ernenwein , S. Eschbach , C. Farnier , S. Fegan , M. V. Fernandes , A. Fiasson , G. Fontaine , S. Funk , M. Füßling , S. Gabici , Y. A. Gallant , T. Garrigoux , F. Gaté , G. Giavitto , D. Glawion , J. F. Glicenstein , D. Gottschall , M. -H. Grondin , J. Hahn , M. Haupt , J. Hawkes , G. Heinzelmann , G. Henri , G. Hermann , J. A. Hinton , W. Hofmann , C. Hoischen , T. L. Holch , M. Holler , D. Horns , A. Ivascenko , H. Iwasaki , A. Jacholkowska , M. Jamrozy , D. Jankowsky , F. Jankowsky , M. Jingo , L. Jouvin , I. Jung-Richardt , M. A. Kastendieck , K. Katarzyński , M. Katsuragawa , U. Katz , D. Kerszberg , D. Khangulyan , B. Khélifi , J. King , S. Klepser , D. Klochkov , W. Kluźniak , Nu. Komin , K. Kosack , S. Krakau , M. Kraus , P. P. Krüger , H. Laffon , G. Lamanna , J. Lau , J. Lefaucheur , A. Lemière , M. Lemoine-Goumard , J. -P. Lenain , E. Leser , T. Lohse , M. Lorentz , R. Liu , R. López-Coto , I. Lypova , D. Malyshev , V. Marandon , A. Marcowith , C. Mariaud , R. Marx , G. Maurin , N. Maxted , M. Mayer , P. J. Meintjes , M. Meyer , A. M. W. Mitchell , R. Moderski , M. Mohamed , L. Mohrmann , K. Morå , E. Moulin , T. Murach , S. Nakashima , M. de Naurois , H. Ndiyavala , F. Niederwanger , J. Niemiec , L. Oakes , P. O'Brien , H. Odaka , S. Ohm , M. Ostrowski , I. Oya , M. Padovani , M. Panter , R. D. Parsons , N. W. Pekeur , G. Pelletier , C. Perennes , P. -O. Petrucci , B. Peyaud , Q. Piel , S. Pita , V. Poireau , D. A. Prokhorov , H. Prokoph , G. Pühlhofer , M. Punch , A. Quirrenbach , S. Raab , R. Rauth , A. Reimer , O. Reimer , M. Renaud , R. de los Reyes , F. Rieger , L. Rinchiuso , C. Romoli , G. Rowell , B. Rudak , C. B. Rulten , V. Sahakian , S. Saito , D. A. Sanchez , A. Santangelo , M. Sasaki , R. Schlickeiser , F. Schüssler , A. Schulz , U. Schwanke , S. Schwemmer , M. Seglar-Arroyo , A. S. Seyffert , N. Shafi , I. Shilon , K. Shiningayamwe. R. Simoni , H. Sol , F. Spanier , M. Spir-Jacob , Ł. Stawarz , R. Steenkamp , C. Stegmann , C. Steppa , I. Sushch , T. Takahashi , J. -P. Tavernet , T. Tavernier , A. M. Taylor , R. Terrier , L. Tibaldo , D. Tiziani , M. Tluczykont , C. Trichard , M. Tsirou , N. Tsuji , R. Tuffs , Y. Uchiyama , D. J. van der Walt , C. van Eldik , C. van Rensburg , B. van Soelen , G. Vasileiadis , J. Veh , C. Venter , A. Viana , P. Vincent , J. Vink , F. Voisin , H. J. Völk , T. Vuillaume , Z. Wadiasingh , S. J. Wagner , P. Wagner , R. M. Wagner , R. White , A. Wierzcholska , P. Willmann , A. Wörnlein , D. Wouters , R. Yang , D. Zaborov , M. Zacharias , R. Zanin , A. A. Zdziarski , A. Zech , F. Zefi , A. Ziegler , J. Zorn , N. Żywucka , Fermi-LAT collaboration , J. D. Magill , S. Buson , C. C. Cheung , J. S. Perkins , Y. Tanaka

The optically thick homogenous SSC model: Application to radio galaxy NGC 1275

We consider the Synchrotron Self-Compton (SSC) model for jets in active galaxies in which produced $\gamma$-ray photons can be absorbed in collisions with the synchrotron radiation already at the emission region. In terms of such modified…

High Energy Astrophysical Phenomena · Physics 2014-09-30 P. Banasinski , W. Bednarek

A spectral hardening in the Fermi-LAT Data of 1ES 0502+675

The $\gamma$-ray spectral feature of the blazar 1ES 0502+675 is investigated by using Fermi Large Area Telescope (Fermi-LAT) Pass 8 data (between 100 MeV and 300 GeV) covering from 2008 August to 2021 April. A significant ($\sim4\sigma$)…

High Energy Astrophysical Phenomena · Physics 2022-01-19 Yuhang Zeng , Dahai Yan , Wen Hu , Jiancheng Wang

Unexpected Dip in the Solar Gamma-Ray Spectrum

The solar disk is a bright source of multi-GeV gamma rays, due to the interactions of hadronic cosmic rays with the solar atmosphere. However, the underlying production mechanism is not understood, except that its efficiency must be greatly…

High Energy Astrophysical Phenomena · Physics 2018-10-09 Qing-Wen Tang , Kenny C. Y. Ng , Tim Linden , Bei Zhou , John F. Beacom , Annika H. G. Peter

Suborbital Fermi/LAT Analysis of the Brightest Gamma-Ray Flare of Blazar 3C 454.3

Recent detection of suborbital gamma-ray variability of Flat Spectrum Radio Quasar (FSRQ) 3C 279 by Fermi Large Area Telescope (LAT) is in severe conflict with established models of blazar emission. This paper presents the results of…

High Energy Astrophysical Phenomena · Physics 2017-12-15 Krzysztof Nalewajko

Anisotropic inverse Compton scattering in powerful radio galaxies: the case of 3C 295

Inverse Compton (IC) scattering of nuclear photons with relativistic electrons in the lobes of powerful radio galaxies and quasars can give detectable extended X-ray emission from the radio lobes if relativistic electrons with a Lorentz…

Astrophysics · Physics 2009-11-06 G. Brunetti , M. Cappi , G. Setti , L. Feretti , D. E. Harris

Cygnus X-3: A variable petaelectronvolt gamma-ray source

We report the discovery of variable $\gamma$-rays up to petaelectronvolt from Cygnus X-3, an iconic X-ray binary. The $\gamma$-ray signal was detected with a statistical significance of approximately 10 $\sigma$ by the Large High Altitude…

High Energy Astrophysical Phenomena · Physics 2026-04-14 The LHAASO Collaboration , Zhen Cao , F. Aharonian , Y. X. Bai , Y. W. Bao , D. Bastieri , X. J. Bi , Y. J. Bi , W. Bian , J. Blunier , A. V. Bukevich , C. M. Cai , Y. Y. Cai , W. Y. Cao , Zhe Cao , J. Chang , J. F. Chang , E. S. Chen , G. H. Chen , H. K. Chen , L. F. Chen , Liang Chen , Long Chen , M. J. Chen , M. L. Chen , Q. H. Chen , S. Chen , S. H. Chen , S. Z. Chen , T. L. Chen , X. B. Chen , X. J. Chen , X. P. Chen , Y. Chen , N. Cheng , Q. Y. Cheng , Y. D. Cheng , M. Y. Cui , S. W. Cui , X. H. Cui , Y. D. Cui , B. Z. Dai , H. L. Dai , Z. G. Dai , Danzengluobu , Y. X. Diao , A. J. Dong , X. Q. Dong , K. K. Duan , J. H. Fan , Y. Z. Fan , J. Fang , J. H. Fang , K. Fang , C. F. Feng , H. Feng , L. Feng , S. H. Feng , X. T. Feng , Y. Feng , Y. L. Feng , S. Gabici , B. Gao , Q. Gao , W. Gao , W. K. Gao , M. M. Ge , T. T. Ge , L. S. Geng , G. Giacinti , G. H. Gong , Q. B. Gou , M. H. Gu , F. L. Guo , J. Guo , K. J. Guo , X. L. Guo , Y. Q. Guo , Y. Y. Guo , R. P. Han , O. A. Hannuksela , M. Hasan , H. H. He , H. N. He , J. Y. He , X. Y. He , Y. He , S. Hernández-Cadena , B. W. Hou , C. Hou , X. Hou , H. B. Hu , S. C. Hu , C. Huang , D. H. Huang , J. J. Huang , X. L. Huang , X. T. Huang , X. Y. Huang , Y. Huang , Y. Y. Huang , A. Inventar , X. L. Ji , H. Y. Jia , K. Jia , H. B. Jiang , K. Jiang , X. W. Jiang , Z. J. Jiang , M. Jin , S. Kaci , M. M. Kang , I. Karpikov , D. Khangulyan , D. Kuleshov , K. Kurinov , Cheng Li , Cong Li , D. Li , F. Li , H. B. Li , H. C. Li , Jian Li , Jie Li , K. Li , L. Li , R. L. Li , S. D. Li , T. Y. Li , W. L. Li , X. R. Li , Xin Li , Y. Li , Zhe Li , Zhuo Li , E. W. Liang , Y. F. Liang , S. J. Lin , B. Liu , C. Liu , D. Liu , D. B. Liu , H. Liu , J. Liu , J. L. Liu , J. R. Liu , M. Y. Liu , R. Y. Liu , S. M. Liu , W. Liu , X. Liu , Y. Liu , Y. Liu , Y. N. Liu , Y. Q. Lou , Q. Luo , Y. Luo , H. K. Lv , B. Q. Ma , L. L. Ma , X. H. Ma , I. O. Maliy , J. R. Mao , Z. Min , W. Mitthumsiri , Y. Mizuno , G. B. Mou , A. Neronov , K. C. Y. Ng , M. Y. Ni , L. Nie , L. J. Ou , Z. W. Ou , P. Pattarakijwanich , Z. Y. Pei , D. Y. Peng , J. C. Qi , M. Y. Qi , J. J. Qin , D. Qu , A. Raza , C. Y. Ren , D. Ruffolo , A. Sáiz , D. Savchenko , D. Semikoz , L. Shao , O. Shchegolev , Y. Z. Shen , X. D. Sheng , Z. D. Shi , F. W. Shu , H. C. Song , Yu. V. Stenkin , V. Stepanov , Y. Su , D. X. Sun , H. Sun , J. X. Sun , Q. N. Sun , X. N. Sun , Z. B. Sun , N. H. Tabasam , J. Takata , P. H. T. Tam , H. B. Tan , Q. W. Tang , R. Tang , Z. B. Tang , W. W. Tian , C. N. Tong , L. H. Wan , C. Wang , D. H. Wang , G. W. Wang , H. G. Wang , J. C. Wang , K. Wang , Kai Wang , Kai Wang , L. P. Wang , L. Y. Wang , L. Y. Wang , R. Wang , W. Wang , X. G. Wang , X. J. Wang , X. Y. Wang , Y. Wang , Y. D. Wang , Z. H. Wang , Z. X. Wang , Zheng Wang , D. M. Wei , J. J. Wei , Y. J. Wei , T. Wen , S. S. Weng , C. Y. Wu , H. R. Wu , Q. W. Wu , S. Wu , X. F. Wu , Y. S. Wu , S. Q. Xi , J. Xia , J. J. Xia , G. M. Xiang , D. X. Xiao , G. Xiao , Y. F. Xiao , Y. L. Xin , H. D. Xing , Y. Xing , D. R. Xiong , B. N. Xu , C. Y. Xu , D. L. Xu , R. F. Xu , R. X. Xu , S. S. Xu , W. L. Xu , L. Xue , D. H. Yan , T. Yan , C. W. Yang , C. Y. Yang , F. F. Yang , L. L. Yang , M. J. Yang , R. Z. Yang , W. X. Yang , Z. H. Yang , Z. G. Yao , X. A. Ye , L. Q. Yin , N. Yin , X. H. You , Z. Y. You , Q. Yuan , H. Yue , H. D. Zeng , T. X. Zeng , W. Zeng , X. T. Zeng , M. Zha , B. B. Zhang , B. T. Zhang , C. Zhang , H. Zhang , H. M. Zhang , H. Y. Zhang , J. L. Zhang , J. Y. Zhang , Li Zhang , P. F. Zhang , R. Zhang , S. R. Zhang , S. S. Zhang , S. Y. Zhang , W. Zhang , W. Y. Zhang , X. Zhang , X. P. Zhang , Yi Zhang , Yong Zhang , Z. P. Zhang , J. Zhao , L. Zhao , L. Z. Zhao , S. P. Zhao , X. H. Zhao , Z. H. Zhao , F. Zheng , T. C. Zheng , B. Zhou , H. Zhou , J. N. Zhou , M. Zhou , P. Zhou , R. Zhou , X. X. Zhou , X. X. Zhou , B. Y. Zhu , C. G. Zhu , F. R. Zhu , H. Zhu , K. J. Zhu , Y. C. Zou , X. Zuo , J. S. Wang

Does the gamma-ray flux of the blazar 3C 454.3 vary on sub-hour timescales?

In the early days of April 2010, the blazar 3C 454.3 (z=0.859) underwent a strong gamma-ray outburst, reaching fluxes (E > 100 MeV) in excess of 10^-5 ph cm^-2 s^-1. The Fermi Gamma ray Space Telescope performed a 200 ks long pointed…

High Energy Astrophysical Phenomena · Physics 2015-05-18 L. Foschini , G. Tagliaferri , G. Ghisellini , G. Ghirlanda , F. Tavecchio , G. Bonnoli

High energy properties of PKS 1830-211

We report on an analysis of X- and $\gamma$-ray observations of PKS 1830-211, based on the long-term campaigns carried out by \emph{INTEGRAL} and COMPTEL. The \emph{INTEGRAL} data currently available present a $33\sigma$ significance…

Astrophysics · Physics 2010-11-11 Shu Zhang , Yu-peng Chen , Werner Collmar , Luigi Foschini , Ti-Pei Li , Diego F. Torres , Jian-Min Wang

The High-Energy Tail of the Galactic Center Gamma-Ray Excess

Observations by the Fermi-LAT have uncovered a bright, spherically symmetric excess surrounding the center of the Milky Way galaxy. The spectrum of the gamma-ray excess peaks sharply at an energy ~2 GeV, exhibiting a hard spectrum at lower…

High Energy Astrophysical Phenomena · Physics 2017-02-28 Tim Linden , Nicholas L. Rodd , Benjamin R. Safdi , Tracy R. Slatyer

Relativistic plasma as the dominant source of the optical continuum emission in the broad-line radio galaxy 3C 120

We report a relation between radio emission in the inner jet of the Seyfert galaxy 3C 120 and optical continuum emission in this galaxy. Combining the optical variability data with multi-epoch high-resolution very long baseline…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 J. Leon-Tavares , A. P. Lobanov , V. H. Chavushyan , T. G. Arshakian , V. T. Doroshenko , S. G. Sergeev , Y. S. Efimov , S. V. Nazarov

High Latitude, Translucent Molecular Clouds as Probes of Local Cosmic Rays

We analyze the gamma-ray emission from 9 high latitude, translucent molecular clouds taken with the Fermi Large Area Telescope (LAT) between 250 MeV and 10 GeV. Observations of gamma-rays allow us to probe the density and spectrum of cosmic…

High Energy Astrophysical Phenomena · Physics 2015-05-27 R. D. Abrahams , T. A. D. Paglione

The origins of the gamma-ray flux variations of NGC 1275 based on 8 years of Fermi-LAT observations

We present an analysis of 8 years of Fermi-LAT ( > 0.1 GeV) gamma-ray data obtained for the radio galaxy NGC 1275. The gamma-ray flux from NGC 1275 is highly variable on short (~ days to weeks) timescales, and has steadily increased over…

High Energy Astrophysical Phenomena · Physics 2018-06-27 K. Tanada , J. Kataoka , M. Arimoto , M. Akita , C. C. Cheung , S. W. Digel , Y. Fukazawa

Search for Gamma-ray Emission from X-ray Selected Seyfert Galaxies with Fermi-LAT

We report on a systematic investigation of the gamma-ray properties of 120 hard X-ray-selected Seyfert galaxies classified as `radio-quiet' objects, utilizing the three-year accumulation of Fermi-LAT data. Our sample of Seyfert galaxies is…

High Energy Astrophysical Phenomena · Physics 2012-03-20 LAT Collaboration

Radio Galaxies Dominate the High-Energy Diffuse Gamma-Ray Background

It has been suggested that unresolved radio galaxies and radio quasars (sometimes referred to as misaligned active galactic nuclei) could be responsible for a significant fraction of the observed diffuse gamma-ray background. In this study,…

High Energy Astrophysical Phenomena · Physics 2016-08-17 Dan Hooper , Tim Linden , Alejandro Lopez

Disk-Jet Connection in the Radio Galaxy 3C 120

We present the results of extensive multi-frequency monitoring of the radio galaxy 3C 120 between 2002 and 2007 at X-ray, optical, and radio wave bands, as well as imaging with the Very Long Baseline Array (VLBA). Over the 5 yr of…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Ritaban Chatterjee , Alan P. Marscher , Svetlana G. Jorstad , Alice R. Olmstead , Ian M. McHardy , Margo F. Aller , Hugh D. Aller , Anne Lahteenmaki , Merja Tornikoski , Talvikki Hovatta , Kevin Marshall , H. Richard Miller , Wesley T. Ryle , Benjamin Chicka , A. J. Benker , Mark C. Bottorff , David Brokofsky , Jeffrey S. Campbell , Taylor S. Chonis , C. Martin Gaskell , Evelina R. Gaynullina , Konstantin N. Grankin , Cecelia H. Hedrick , Mansur A. Ibrahimov , Elizabeth S. Klimek , Amanda K. Kruse , Shoji Masatoshi , Thomas R. Miller , Hong-Jian Pan , Eric A. Petersen , Bradley W. Peterson , Zhiqiang Shen , Dmitriy V. Strelnikov , Jun Tao , Aaron E. Watkins , Kathleen Wheeler