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Related papers: Basic properties of Gamma-ray loud blazars

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We determined the basic parameters, such as the central black hole mass ($M$), the boosting factor (or Doppler factor) ($\delta$), the propagation angle ($\Phi$) and the distance along the axis to the site of $\gamma$-ray production ($d$)…

Astrophysics · Physics 2009-11-10 J. H. Fan

Aiming to delineate the physical framework of blazars, we present an effective method to estimate four important parameters based on the idea proposed by \citet{BK95}, including the upper limit of central black hole mass $M$, the Doppler…

High Energy Astrophysical Phenomena · Physics 2022-02-02 Zhiyuan Pei , Junhui Fan , Jianghe Yang , Danyi Huang , Ziyan Li

We develop a general expression for the gamma-gamma absorption coefficient for gamma-rays propagating in an arbitrary direction at an arbitrary point in space above an X-ray emitting accretion disk. The X-ray intensity is assumed to vary as…

Astrophysics · Physics 2009-10-28 Peter A. Becker , Menas Kafatos

We present the results of a multi-frequency, time-averaged analysis of blazars included in the Candidate Gamma-ray Blazar Survey catalog. Our sample consists of 324 $\gamma$-ray detected ($\gamma$-ray loud) and 191 non $\gamma$-ray detected…

High Energy Astrophysical Phenomena · Physics 2017-12-20 Vaidehi S. Paliya , L. Marcotulli , M. Ajello , M. Joshi , S. Sahayanathan , A. R. Rao , D. Hartmann

The sizes of the broad-line regions (BLRs) in $\gamma$-ray active galactic nuclei (AGNs) are estimated from their optical continuum luminosity by using the empirical relation between $R_{\rm BLR}$ and $L_{\lambda,\rm opt}$. Using the broad…

Astrophysics · Physics 2009-11-10 Zhong-Hui Fan , Xinwu Cao

In this paper, The central black hole masses and the Doppler factors are derived for PKS 0528+134, PKS 0537-441, 3C279, PKS 1406-074, PKS 1622-297, Q1633+382, Mkn 501, and BL Lacertae. The masses obtained are in the range of (1 -7)$\times…

Astrophysics · Physics 2009-10-31 J. H. Fan , G. Z. Xie , R. Bacon

We study the broad emission line blazars detected in the gamma-ray band by the Large Area Telescope onboard the Fermi satellite and with the optical spectrum studied by Shaw et al. (2012, 2013). The observed broad line strength provides a…

High Energy Astrophysical Phenomena · Physics 2015-06-23 G. Ghisellini , F. Tavecchio

The detection of high-redshift ($z>$3) blazars enables the study of the evolution of the most luminous relativistic jets over cosmic time. More importantly, high-redshift blazars tend to host massive black holes and can be used to constrain…

High Energy Astrophysical Phenomena · Physics 2017-04-25 Large Area Telescope Collaboration

Beaming effect is important for the observational properties of blazars. In this work, we collect 91 $Fermi$ blazars with available radio Doppler factors. $\gamma$-ray Doppler factors are estimated and compared with radio Doppler factors…

High Energy Astrophysical Phenomena · Physics 2017-07-19 C. Lin , J. H. Fan , H. B. Xiao

We have analyzed a large sample of clean blazars detected by Fermi Large Area Telescope (LAT). Using literature and calculation, we obtained intrinsic $\gamma$-ray luminosity excluding beaming effect, black hole mass, broad-line luminosity…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Dingrong Xiong , Xiong Zhang

We study a sample of 30 high-redshift blazars ($z>2.5$) by means of spectra and the radiation mechanism with Fermi Large Area Telescope $\gamma$-ray observations spanning 15 years. Three models -- the power law, power law with an…

High Energy Astrophysical Phenomena · Physics 2025-01-27 Fan Wu , Benzhong Dai

We investigate the dependence of gamma-ray brightness of blazars on intrinsic properties of their parsec-scale radio jets and the implication for relativistic beaming. By combining apparent jet speeds derived from high-resolution VLBA…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 T. Savolainen , D. C. Homan , T. Hovatta , M. Kadler , Y. Y. Kovalev , M. L. Lister , E. Ros , J. A. Zensus

Relativistic jets from accreting supermassive black holes at cosmological distances can be powerful emitters of $\gamma$-rays. However, the precise mechanisms and locations responsible for the dissipation of energy within these jets,…

High Energy Astrophysical Phenomena · Physics 2025-01-03 Sushmita Agarwal , Amit Shukla , Karl Mannheim , Bhargav Vaidya , Biswajit Banerjee

We study the properties of a significant thermal emission component that was identified in 47 GRBs observed by different instruments. Within the framework of the "fireball" model, we deduce the values of the Lorentz factor Gamma, and the…

High Energy Astrophysical Phenomena · Physics 2015-11-11 Asaf Pe'er , Hugh Barlow , Shane O'Mahony , Raffaella Margutti , Felix Ryde , Josefin Larsson , Davide Lazzatti , Mario Livio

The ultraviolet (UV) spectra of 16 blazars (<z> ~1) from the archives of the Hubble Space Telescope Faint Object Spectrograph have been analyzed in order to study in a systematic way the properties oftheir broad UV emission lines. We find…

Astrophysics · Physics 2009-11-13 Elena Pian , Renato Falomo , Aldo Treves

Blazars are a subclass of active galactic nuclei (AGNs) with extreme observation properties, which is caused by the beaming effect, expressed by a Doppler factor, in a relativistic jet. Doppler factor is an important parameter in the…

High Energy Astrophysical Phenomena · Physics 2020-10-21 Zhiyuan Pei , Junhui Fan , Jianghe Yang , Denis Bastieri

Blazar radiation is dominated by a relativistic jet which can be modeled at first approximation using just two intrinsic parameters - the Lorentz factor $\Gamma$ and the viewing angle $\theta$. Blazar jet observations are often beamed due…

High Energy Astrophysical Phenomena · Physics 2016-06-29 Payaswini Saikia , Elmar Körding , Heino Falcke

In this paper, we study the photon-photon pair production optical depth for gamma-rays with energies from 10 to 200 GeV emitted by powerful blazars due to the diffuse radiation field of broad line region (BLR). There are four key parameters…

Astrophysics · Physics 2014-01-10 H. T. Liu , J. M. Bai

Blazars are a sub-category of radio-loud active galactic nuclei with relativistic jets pointing towards to the observer. They are well-known for their non-thermal variable emission, which practically extends over the whole electromagnetic…

High Energy Astrophysical Phenomena · Physics 2019-01-28 Stella Boula , Maria Petropoulou , Apostolos Mastichiadis

Blazar spectral models generally have numerous unconstrained parameters, leading to ambiguous values for physical properties like Doppler factor delta or fluid magnetic field B'. To help remedy this problem, a few modifications of the…

High Energy Astrophysical Phenomena · Physics 2015-06-15 Charles D. Dermer , Matteo Cerruti , Benoit Lott , Catherine Boisson , Andreas Zech
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