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Related papers: Broadband Spectral Fitting of Blazars using XSPEC

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Blazars' non-thermal emission shows rapid variability across all wavelengths, so spectral energy distributions (SEDs) built from quasi-simultaneous data are crucial for revealing the jets physical properties. In this work, we construct…

High Energy Astrophysical Phenomena · Physics 2026-05-22 Yi Zhong , Zhujian Wan , Rui Xue , Hubing Xiao , Dingrong Xiong , Ze-Rui Wang

Context: Being dominated by non-thermal emission from aligned relativistic jets, blazars allow us to elucidate the physics of extragalactic jets, and, ltimately, how the energy is extracted from the central black hole in radio-loud active…

We model simultaneous or quasi-simultaneous multi-band spectral energy distributions (SEDs) for a sample of 25 blazars that have radio core-shift measurements, where a one-zone leptonic model and Markov chain Monte Carlo technique are…

High Energy Astrophysical Phenomena · Physics 2018-01-16 Linhui Wu , Qingwen Wu , Dahai Yan , Liang Chen , Xuliang Fan

We perform a detailed spectral study of a recent flaring activity from the Flat Spectrum Radio Quasar (FSRQ), 3C\,454.3, observed simultaneously in optical, UV, X-ray and $\gamma$-ray energies during 16 to 28 August, 2015. The source…

High Energy Astrophysical Phenomena · Physics 2017-05-18 Zahir Shah , S. Sahayanathan , Nijil Mankuzhiyil , Pankaj Kushwaha , Ranjeev Misra , Naseer Iqbal

We present a time-resolved X-ray spectral study of the high energy peaked blazar Mkn 421 using simultaneous broadband observations from the LAXPC and SXT instruments on-board AstroSat. The ~ 400 ksec long observation taken during 3-8…

Astrophysics of Galaxies · Physics 2021-10-20 Jyotishree Hota , Zahir Shah , Rukaiya Khatoon , Ranjeev Misra , Ananta C. Pradhan , Rupjyoti Gogoi

Blazars, a highly energetic subclass of jetted active galactic nuclei, show a broad band spectral energy distribution (SED) with two bumps, resulting from non-thermal jet emission. In 1998, an anticorrelation between the SED luminosity and…

High Energy Astrophysical Phenomena · Physics 2025-06-24 I. Viale , E. Prandini , C. Righi , F. Bovolon , N. Sahakyan

Single-zone synchrotron self-Compton and external Compton models are widely used to explain broad-band Spectral Energy Distributions (SEDs) of blazars from infrared to gamma-rays. These models bear obvious similarities to the homogeneous…

The BL Lac object 3C 66A was observed in an extensive multiwavelength monitoring campaign from July 2003 till April 2004. The spectral energy distribution (SED) was measured over the entire electromagnetic spectrum, with flux measurements…

Astrophysics · Physics 2009-06-23 M. Joshi , M. Boettcher

We report on X-ray measurements constraining the spectral energy distribution (SED) of the high-redshift $z=5.18$ blazar SDSS J013127.34$-$032100.1 with new XMM-Newton and NuSTAR exposures. The blazar's X-ray spectrum is well fit by a power…

High Energy Astrophysical Phenomena · Physics 2020-11-25 Hongjun An , Roger W. Romani

A study of blazar PKS 1424-418 was carried out using multi waveband data collected by Fermi-LAT, Swift-XRT, Swift-UVOT and SMARTS telescopes between MJD 56000 to MJD 56600 (14 Mar 2012 to 4 Nov 2013). Two flaring episodes were identified by…

High Energy Astrophysical Phenomena · Physics 2021-01-18 Jayant Abhir , Jophin Joseph , Sonal R Patel , Debanjan Bose

In this review, recent progress in theoretical models for the broadband (radio through gamma-ray) emission from blazars are summarized. The salient features of both leptonic and hadronic models are reviewed. I present sample modeling…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-03 Markus Boettcher

We collect data from the radio to the gamma-ray range for three complete samples of blazars: the Slew Survey and the 1Jy samples of BL Lacs and the 2Jy sample of Flat Spectrum Radio-Loud Quasars (FSRQs). The fraction of objects detected in…

Astrophysics · Physics 2009-10-30 G. Fossati , L. Maraschi , A. Celotti , A. Comastri , G. Ghisellini

Blazars host the most powerful persistent relativistic conical jet -- a highly collimated anisotropic flow of material/plasma. Motivated by this, we explore the blazar's broadband spectral energy distribution (SED) in an anisotropic flow of…

High Energy Astrophysical Phenomena · Physics 2021-06-14 Nagendra Kumar , Pankaj Kushwaha

The physics-determined broadband spectral energy distributions (SEDs) of blazars have been widely used to study the property during their flaring/outburst states, while the non-flaring state takes up most of their lifetime and the general…

High Energy Astrophysical Phenomena · Physics 2025-09-16 Hubing Xiao , Haitao Cao , Rui Xue , Zhihao Ouyang , Shaohua Zhang , Junping Chen , Zhijian Luo , Jianghe Yang , Junhui Fan

The SED of blazars show significant curvature. In this paper, we study the curvature properties for a large sample of Fermi/LAT bright blazars based on quasi-simultaneous SED. Both SEDs of synchrotron and inverse Compton (IC) components are…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Liang Chen

The one-zone synchrotron-self-Compton (SSC) model aims to describe the spectral energy distribution (SED) of BL Lac objects via synchrotron emission by a non-thermal population of electrons and positrons in a single homogeneous emission…

High Energy Astrophysical Phenomena · Physics 2013-08-19 Matteo Cerruti , Catherine Boisson , Andreas Zech

Interpreting the spectral energy distributions (SEDs) of astrophysical objects with physically motivated models is computationally expensive. These models require solving coupled differential equations in high-dimensional parameter spaces,…

In this review, recent progress in theoretical models for blazar emission will be summarized. The salient features of both leptonic and lepto-hadronic approaches to modeling blazar spectral energy distributions will be reviewed. I will…

High Energy Astrophysical Phenomena · Physics 2010-06-28 Markus Boettcher

Blazars are among the most studied sources in high-energy astrophysics as they form the largest fraction of extragalactic gamma-ray sources and are considered prime candidates for being the counterparts of high-energy astrophysical…

Aim : The nearby TeV blazar 1ES 1959+650 (z=0.047) was reported to be in flaring state during June - July 2016 by Fermi-LAT, FACT, MAGIC and VERITAS collaborations. We studied the spectral energy distributions (SEDs) in different states of…

High Energy Astrophysical Phenomena · Physics 2018-03-21 S. R. Patel , A. Shukla , V. R. Chitnis , D. Dorner , K. Mannheim , B. S. Acharya , B. J. Nagare