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Related papers: Broadband Spectral Fitting of Blazars using XSPEC

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We combined multi-wavelength data for blazars from the Roma-BZCAT catalog and analyzed hundreds of X-ray spectra. We present the fluxes and Spectral Energy Distributions (SEDs), in 12 frequency bands from radio to $\gamma$-rays, for a final…

Astrophysics of Galaxies · Physics 2016-06-17 Peiyuan Mao , C. Megan Urry , Francesco Massaro , Alessandro Paggi , Joe Cauteruccio , Soren R. Künzel

We study the quasi-simultaneous Spectral Energy Distributions (SED) of 48 LBAS blazars, collected within three months of the Fermi LAT Bright AGN Sample (LBAS) data taking period, combining Fermi and Swift data with radio NIR-Optical and…

High Energy Astrophysical Phenomena · Physics 2009-12-21 S. Raino' , E. Cavazzuti , S. Colafrancesco , P. Giommi , A. Tramacere , the Fermi-LAT Collaboration

We report on the variations of the physical parameters of the jet observed in the blazar Mrk 421, and discuss the origin of X-ray flares in the jet, based on the analysis of the several spectral energy distributions (SEDs). The SEDs are…

High Energy Astrophysical Phenomena · Physics 2020-05-27 Yurika Yamada , Makoto Uemura , Ryosuke Itoh , Yasushi Fukazawa , Masanori Ohno , Fumiya Imazato

Multiwavelength observations are now the norm for studying blazars' various states of activity, classifying them, and determining possible underlying physical processes driving their emission. Broadband emission models became unavoidable…

High Energy Astrophysical Phenomena · Physics 2023-10-24 Olivier Hervet , Caitlin A. Johnson , Adrian Youngquist

This study examines the characterization of binary star systems using Spectral Energy Distributions (SEDs), a technique increasingly essential with the rise of large-scale astronomical surveys. Binaries can emit flux at different regions of…

Solar and Stellar Astrophysics · Physics 2025-03-20 Vikrant V. Jadhav

The origin of gamma-ray flares observed from blazars is one of the major mysteries in jet physics. We have attempted to address this problem following a novel spectral energy distribution (SED) fitting technique that explored the flaring…

High Energy Astrophysical Phenomena · Physics 2021-12-08 Vaidehi S. Paliya , Markus Boettcher , Mark Gurwell , C. S. Stalin

We present long-term multiwavelength observations of blazar CTA 102 ($z=1.037$). Detailed temporal and spectral analyses of $\gamma$-ray, X-ray and UV/optical data observed by {\it Fermi}-LAT, Swift XRT, NuSTAR and Swift-UVOT over a period…

High Energy Astrophysical Phenomena · Physics 2022-10-26 N. Sahakyan , D. Israyelyan , G. Harutyunyan , S. Gasparyan , V. Vardanyan , M. Khachatryan

We present simultaneous optical and X-ray data from Swift for a sample of FSRQs selected from the EMSS survey. We present also a complete analysis of Swift and INTEGRAL data on 4 blazars recently discussed as possibly challenging the trends…

Astrophysics · Physics 2009-11-13 L. Maraschi , L. Foschini , G. Ghisellini , F. Tavecchio , R. M. Sambruna

Transition blazars exhibit a shift from one subclass to the next during different flux states. It is therefore crucial to study them to understand the underlying physics of blazars. We probe the origin of the multi-wavelength emission from…

High Energy Astrophysical Phenomena · Physics 2023-11-17 Ashwani Pandey , Pankaj Kushwaha , Paul J. Wiita , Raj Prince , Bozena Czerny , C. S. Stalin

(Abridged) In this paper, multi-wavelength data are compiled for a sample of 1425 Fermi blazars to calculate their spectral energy distributions (SEDs). A parabolic function, $\log(\nu F_{\nu}) = P_1(\log\nu - P_2)^2 + P_3,$ is used for SED…

High Energy Astrophysical Phenomena · Physics 2016-10-19 J. H. Fan , J. H. Yang , Y. Liu , G. Y. Luo , C. Lin , Y. H. Yuan , H. B. Xiao , A. Y. Zhou , T. X. Hua , Z. Y. Pei

Blazars research is one of the hot topics of contemporary extra-galactic astrophysics. That is because these sources are the most abundant type of extra-galactic gamma-ray sources and are suspected to play a central role in multi-messenger…

We present the results of our study of spectral energy distributions (SEDs) of a sample of ten low- to intermediate-synchrotron-peaked blazars. We investigate some of the physical parameters most likely responsible for the observed…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Bindu Rani , Alok C. Gupta , R. Bachev , A. Strigachev , E. Semkov , F. D'Ammando , P. J. Wiita , M. A. Gurwell , E. Ovcharov , B. Mihov , S. Boeva , S. Peneva

In the context of modeling spectral energy distributions (SEDs) for blazars, we extend the method that uses a convolutional neural network (CNN) to include external inverse Compton processes. The model assumes that relativistic electrons…

High Energy Astrophysical Phenomena · Physics 2024-02-13 N. Sahakyan , D. Bégué , A. Casotto , H. Dereli-Bégué , P. Giommi , S. Gasparyan , V. Vardanyan , M. Khachatryan , A. Pe'er

We present a comprehensive temporal and spectral analysis of a few blazars using multi-wavelength observations. Rapid flux variations are quantified via the doubling/halving timescale method, revealing the shortest variability timescales of…

High Energy Astrophysical Phenomena · Physics 2025-06-17 Ajay Sharma , Aishwarya Sarath , Sakshi Chaudhary , Debanjan Bose

The X-ray spectrum of extreme HBL type blazars is located in the synchrotron branch of the broadband spectral energy distribution (SED), at energies below the peak. A joint fit of the extrapolated X-ray spectra together with a host galaxy…

High Energy Astrophysical Phenomena · Physics 2020-06-10 Alicja Wierzcholska , Stefan Wagner

The long term broadband spectral study of Flat Spectrum Radio Quasars during different flux states has the potential to infer the emission mechanisms and the cause of spectral variations. To scrutinize this, we performed a detailed…

High Energy Astrophysical Phenomena · Physics 2023-10-11 Aminabi Thekkoth , S. Sahayanathan , Zahir Shah , Vaidehi S. Paliya , C. D. Ravikumar

The emission from blazars is known to be variable at all wavelengths. The flux variability is often accompanied by spectral changes. Spectral energy distribution (SED) changes must be associated with changes in the spectra of emitting…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 B. Rani , Alok C. Gupta , Paul J. Wiita

The overall spectra (SED) of blazars, from radio to gamma-ray energies, seem to obey well defined trends, with a continuity of properties between blazars of different classes. To quantify this statement we can either investigate their…

Astrophysics · Physics 2007-05-23 Gabriele Ghisellini

The X-ray spectral curvature of blazars is traditionally explained by an empirical log-parabola function characterized by three parameters, namely the flux, curvature and spectral index at a given energy. Since their exact relationship with…

High Energy Astrophysical Phenomena · Physics 2018-08-08 Pranjupriya Goswami , Sunder Sahayanathan , Atreyee Sinha , Ranjeev Misra , Rupjyoti Gogoi

(Abridged) We have conducted a detailed investigation of the broad-band spectral properties of the \gamma-ray selected blazars of the Fermi LAT Bright AGN Sample (LBAS). By combining our accurately estimated Fermi gamma-ray spectra with…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 A. A. Abdo , M. Ackermann , M. Ajello , M. Axelsson , L. Baldini , J. Ballet , G. Barbiellini , D. Bastieri , B. M. Baughman , K. Bechtol , R. Bellazzini , B. Berenji , R. D. Blandford , E. D. Bloom , E. Bonamente , A. Borgland , J. Bregeon , A. Brez , M. Brigida , P. Bruel , T. H. Burnett , S. Buson , G. A. Caliandro , R. A. Cameron , P. A. Caraveo , J. M. Casandjian , E. Cavazzuti , C. Cecchi , O. Celik , E. Charles , S. Chaty , A. Chekhtman , J. Chiang , S. Ciprini , R. Claus , J. Cohen-Tanugi , S. Colafrancesco , L. R. Cominsky , J. Conrad , L. Costamante , S. Cutini , C. D. Dermer , A. de Angelis , F. de Palma , S. W. Digel , E. do Couto e Silva , P. S. Drell , R. Dubois , D. Dumora , C. Farnier , C. Favuzzi , S. J. Fegan , W. B. Focke , P. Fortin , M. Frailis , L. Fuhrmann , Y. Fukazawa , S. Funk , P. Fusco , F. Gargano , D. Gasparrini , N. Gehrels , S. Germani , B. Giebels , N. Giglietto , P. Giommi , F. Giordano , T. Glanzman , G. Godfrey , I. A. Grenier , J. E. Grove , L. Guillemot , S. Guiriec , D. Hadasch , Y. Hanabata , A. K. Harding , M. Hayashida , E. Hays , S. E. Healey , D. Horan , R. E. Hughes , R. Itoh , M. S. Jackson , G. Johannesson , A. S. Johnson , W. N. Johnson , M. Kadler , T. Kamae , H. Katagiri , J. Kataoka , N. Kawai , M. Kerr , J. Knodlseder , M. L. Kocian , M. Kuss , J. Lande , L. Latronico , F. Longo , F. Loparco , B. Lott , M. N. Lovellette , P. Lubrano , G. M. Madejski , A. Makeev , W. Max-Moerbeck , M. N. Mazziotta , W. McConville , J. E. McEnery , C. Meurer , P. F. Michelson
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