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Related papers: A simplified view of blazars: the gamma-ray case

200 papers

We report on HET and Palomar 5 m spectroscopy of recently identified $\gamma$-ray blazars in the {\it Fermi} LAT Bright Source List. These data provide identifications for 10 newly discovered $\gamma$-ray flat spectrum radio quasars (FSRQ)…

High Energy Astrophysical Phenomena · Physics 2015-05-14 Michael S. Shaw , Roger W. Romani , Stephen E. Healey , Garret Cotter , Peter F. Michelson , Anthony C. S. Readhead

Statistical analyses are invaluable methods used to understand intrinsic emission processes and the unification of extragalactic radio sources. In this paper, we collected radio, X-ray and {\gamma}-ray data of blazars from the Fermi-LAT and…

High Energy Astrophysical Phenomena · Physics 2021-12-08 E. U. Iyida , I. O. Eya , F. C. Odo

We use the distributions of spectral indices of a large homogenous sample of Fermi-detected blazars to re-investigate the relationship between flat spectrum radio quasars (FSRQs) and subclasses of BL Lac objects (BL Lacs). We compute the…

High Energy Astrophysical Phenomena · Physics 2020-07-20 E. U. Iyida , F. C. Odo , A. E. Chukwude , A. A. Ubachukwu

We propose and test a fairly simple idea that could account for the blazar sequence: all jets are launched with similar energy per baryon, independently of their power. For instance, flat-spectrum radio quasars (FSRQs), the most powerful…

High Energy Astrophysical Phenomena · Physics 2021-01-13 Jesús M. Rueda-Becerril , Amanda O. Harrison , Dimitrios Giannios

We study the BL Lac objects detected in the one year all sky survey of the Fermi satellite, with a energy spectral slope alpha_gamma in the [0.1-100 GeV] band greater than 1.2. In the alpha_gamma vs gamma-ray luminosity plane, these BL Lacs…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 G. Ghisellini , F. Tavecchio , L. Foschini , G. Ghirlanda

ROSAT observations of a large sample of bright gamma-ray (E > 100 MeV) blazars are presented. Results of a detailed spectral analysis in the soft $\sim$ 0.1-2.0 keV energy range are discussed in relation to the overall energy distribution…

Astrophysics · Physics 2016-08-30 A. Comastri , G. Fossati , G. Ghisellini , S. Molendi

We aim to test if a blazar candidate of uncertain-type (BCU) in the third Fermi active galactic nuclei catalog (3LAC) can be potentially classified as a BL Lac object or a flat spectrum radio quasar (FSRQ) by performing a statistical…

High Energy Astrophysical Phenomena · Physics 2017-03-29 Ting-Feng Yi , Jin Zhang , Rui-Jing Lu , Rui Huang , En-Wei Liang

Flat spectrum radio quasars (FSRQs) are bright active galactic nuclei surrounded by gas clouds within a UV-visible intense radiation field that form the so-called broad line region (BLR). These objects emit relativistic jets from a region…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Richard J. G. Britto , Soebur Razzaque , Benoît Lott

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

We present the redshift evolutions and distributions of the gamma-ray luminosity and photon spectral index of flat spectrum radio quasar (FSRQ) type blazars, using non-parametric methods to obtain the evolutions and distributions directly…

High Energy Astrophysical Phenomena · Physics 2015-06-19 J. Singal , A. Ko , V. Petrosian

The gamma-ray emission offers a powerful diagnostic tool to probe jets and their surroundings in flat spectrum radio quasars (FSRQ). In particular, sources emitting at high energies (>10 GeV) give us the strongest constraints. This…

High Energy Astrophysical Phenomena · Physics 2015-06-18 L. Pacciani , F. Tavecchio , I. Donnarumma , A. Stamerra , L. Carrasco , E. Recillas , A. Porras , M. Uemura

Context. Blazars are a distinct subclass of active galactic nuclei (AGN), known for their fast variability, high polarization, and intense emission across the electromagnetic spectrum, from radio waves to gamma rays. Gamma-ray blazar…

High Energy Astrophysical Phenomena · Physics 2025-01-08 N. Álvarez Crespo , A. Domínguez , V. S. Paliya , M. Chamorro Cazorla , P. Sánchez Blázquez , A. Gil de Paz

The radio properties of blazars detected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope have been observed as part of the VLBA Imaging and Polarimetry Survey (VIPS). This large, flux-limited sample of active…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 J. D. Linford , G. B. Taylor , R. Romani , S. E. Healey , J. F. Helmboldt , A. C. S. Readhead , R. Reeves , J. Richards , G. Cotter

We used the data from the Fermi Gamma-ray Space Telescope to characterise the {\gamma}-ray flux variability of blazars on month-like time scales. Our sample consists of 1120 blazars of which 481 are flat spectrum radio quasars (FSRQs) and…

High Energy Astrophysical Phenomena · Physics 2020-02-12 Bhoomika Rajput , C. S. Stalin , Suvendu Rakshit

We have utilized the largest sample of $\gamma$-ray selected Fermi flat-spectrum radio quasars (FSRQs) ever used (519 sources) to construct the luminosity function and its evolution through the cosmic history. In addition to spanning large…

High Energy Astrophysical Phenomena · Physics 2025-12-02 Garima Rajguru , Lea Marcotulli , Marco Ajello , Mattia Di Mauro , Meg Urry

We present a temporal and spectral analysis of the gamma-ray flux from nine of the brightest flat spectrum radio quasars (FSRQs) detected with the Fermi Large Area Telescope (LAT) during its first eight years of operation, with the aim of…

High Energy Astrophysical Phenomena · Physics 2020-11-20 Atreya Acharyya , Paula M. Chadwick , Anthony M. Brown

The gamma-ray emission from Flat Spectrum Radio Quasars (FSRQs), a sub-class of blazars, is believed to be generated through interactions of high-energy leptons and/or hadrons in the jet with the ambient photon fields, including those from…

High Energy Astrophysical Phenomena · Physics 2025-02-07 Anton Dmytriiev , Atreya Acharyya , Markus Böttcher

Historically, the blazar population has been poorly understood at low frequencies because survey sensitivity and angular resolution limitations have made it difficult to identify megahertz counterparts. We used the LOFAR Two-Metre Sky…

Blazars constitute the most enigmatic class of extragalactic gamma-ray sources, and their observational features have been ascribed to a relativistic jet closely aligned to the line of sight. They are generally divided in two main classes:…

High Energy Astrophysical Phenomena · Physics 2015-06-04 R. D'Abrusco , F. Massaro. M. Ajello , J. E. Grindlay , H. A. Smith , G. Tosti

In this paper we present a statistical analysis of the gamma-ray spectra of flat-spectrum radio quasars (FSRQ) compared to those of BL Lacs. The average spectra and possible systematic deviations from power-law behaviour are investigated by…

Astrophysics · Physics 2009-10-30 M. Pohl , R. C. Hartman , B. B. Jones , P. Sreekumar