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Related papers: An evolutionary scenario for blazar unification

200 papers

Active galactic nuclei (AGNs) can power relativistic jets, which are called blazars when pointed close to our line of sight. Depending on the presence or absence of emission lines in their optical spectra, blazars are categorized into flat…

High Energy Astrophysical Phenomena · Physics 2024-04-23 Garima Rajguru , L. Marcotulli , M. Ajello , A. Tramacere

Blazars are conventionally classified into BL Lac objects and flat-spectrum radio quasars (FSRQs), commonly associated with radiatively inefficient and efficient accretion onto supermassive black holes, respectively. Increasing evidence,…

High Energy Astrophysical Phenomena · Physics 2026-05-18 Javaid Tantry , Naseer Iqbal

The extragalactic $\gamma$-ray sky is dominated by blazars and their study plays an important role in understanding jet physics, cosmic evolution history and origin of ultra high energy cosmic rays. In this work, we study a large sample of…

High Energy Astrophysical Phenomena · Physics 2022-05-23 Muhammad Shahzad Anjum , Liang Chen , Minfeng Gu

The spectral energy distribution and variability of several blazars (Mkn 501, 1 ES 2344+51.4, PKS 2155-30.4, 1 ES 1218+30.4, 3C 454.3) along the blazar sequence is investigated using a selfconsistent and timedependent lepto-hadronic hybrid…

High Energy Astrophysical Phenomena · Physics 2011-09-12 Matthias Weidinger , Felix Spanier

We examine whether Flat Spectrum Radio Quasars (FSRQs) and BL Lacertae objects (BL Lacs) can act as plausible astrophysical sources of diffuse ultra-high-energy cosmic rays (UHECRs). Using realistic luminosity-dependent density evolution…

High Energy Astrophysical Phenomena · Physics 2026-05-20 Swaraj Pratim Sarmah , Umananda Dev Goswami

In the first of a series of papers investigating emission from blazar jets from radio to high-energy {\gamma}-rays, we revisit the class of models where the jet has a uniform conical ballistic structure. We argue that by using simple…

High Energy Astrophysical Phenomena · Physics 2012-12-13 William J. Potter , Garret Cotter

Using three complete, radio flux limited, blazar samples we compare the LogN-LogS and the preliminary radio luminosity function of the general population of BL Lacs to those of the subclass of high energy synchrotron peaked (HBL) BL Lacs.…

Astrophysics · Physics 2007-05-23 P. Giommi , P. Padovani , M. Perri , H. Landt , E. Perlman

The past 20 years have seen phenomenal progress in our understanding of BL Lac objects. They form part of the blazar class, which are radio-loud AGN whose relativistic jets are aligned along our line of sight. Several critical milestones…

Astrophysics · Physics 2007-05-23 C. Megan Urry

Our understanding of the unification of jetted AGN has evolved greatly as jet samples have increased in size. Here, based on the largest-ever sample of over 2000 well-sampled jet spectral energy distributions, we examine the synchrotron…

Astrophysics of Galaxies · Physics 2021-05-12 Mary Keenan , Eileen T. Meyer , Markos Georganopoulos , Karthik Reddy , Omar J. French

Blazar spectra are one of the most important windows into the physical processes occurring along jets. The spectrum, composed from the different emitting regions along the jet, allows us to constrain the physical conditions in the jet. I…

High Energy Astrophysical Phenomena · Physics 2015-06-17 William J. Potter , Garret Cotter

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

Flat Spectrum Radio Quasars (FSRQs) and BL Lac objects detected in the first three months of the Fermi survey neatly separate in the gamma-ray spectral index vs gamma-ray luminosity plane. BL Lac objects are less luminous and have harder…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 G. Ghisellini , L. Maraschi , F. Tavecchio

We present the first deep VLA radio images of flat-spectrum radio quasars (FSRQ) with multiwavelength emission properties similar to those of BL Lacs with synchrotron X-rays. Our observations of twenty-five of these sources show that their…

Astrophysics · Physics 2009-11-13 Hermine Landt , Eric S. Perlman , Paolo Padovani

The synchrotron reflection scenario recently proposed to explain $\gamma$-ray flares observed from blazar jets is studied. Our analysis takes into account the angular distribution of the beamed radiation, the finite extent of the scattering…

Astrophysics · Physics 2016-11-23 M. Boettcher , C. D. Dermer

Blazars are a subclass of radio-loud active galactic nuclei (AGNs), where the jet is aligned close to the line of sight. Blazars emission is dominated by non-thermal processes, where Doppler boosted radiation originates from a relativistic…

High Energy Astrophysical Phenomena · Physics 2021-08-19 Jakub Juryšek , Vitalii Sliusar , Dimitri Moulin , Roland Walter

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

High Energy Astrophysical Phenomena · Physics 2021-08-06 Stela S. Boula , Apostolos Mastichiadis , Demosthenes Kazanas

We perform time-dependent, spatially-resolved simulations of blazar emission to evaluate several flaring scenarios related to magnetic-field amplification and enhanced particle acceleration. The code explicitly accounts for…

The most extreme active galactic nuclei (AGN) are the radio active ones whose relativistic jet propagates close to our line of sight. These objects were first classified according to their emission line features into flat-spectrum radio…

High Energy Astrophysical Phenomena · Physics 2021-01-08 Jesus M. Rueda-Becerril , Amanda O. Harrison , Dimitrios Giannios

The Fermi-LAT survey provides a large sample of blazars selected on the strength of their inverse Compton emission. We cross-correlate the first Fermi-LAT catalogue with the CRATES radio catalogue and use this sample to investigate whether…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-28 J. A. Gupta , I. W. A. Browne , M. W. Peel

We use statistical results from a large sample of about 500 blazars, based on two surveys, the Deep X-ray Radio Blazar Survey (DXRBS), nearly complete, and the RASS-Green Bank survey (RGB), to provide new constraints on the spectral energy…

Astrophysics · Physics 2009-11-07 P. Padovani , E. Perlman , H. Landt , P. Giommi , M. Perri