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Related papers: Fermi/LAT broad emission line blazars

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The width of the broad emission lines in quasars is commonly characterized either by the full-width-at-half-maximum (FWHM) or the square root of the second moment of the line profile ($\sigma_{\rm line}$), and used as an indicator of the…

Based on the classical unification, blazars, namely BL Lacertae objects (BL Lacs) and flat-spectrum radio quasars (FSRQs), are believed to correspond with radio galaxies when observed at small jet viewing angles. In this paper, we aim to…

High Energy Astrophysical Phenomena · Physics 2026-04-01 Xu-Hong Ye , Ranieri D. Baldi , Wen-Xin Yang , Jing-Tian Zhu , Denis Bastieri , Rumen S. Bachev , Anton A. Strigachev , Jun-Hui Fan

We explore the connection between the black hole mass and its relativistic jet for a sample of radio-loud AGN (z < 1), in which the relativistic jet parameters are well estimated by means of long term monitoring with the 14m Mets\"ahovi…

Astrophysics of Galaxies · Physics 2015-06-24 A. Olguín-Iglesias , J. León-Tavares , V. Chavushyan , E. Valtaoja , C. Añorve , K. Nilsson , J. Kotilainen , M. Tornikoski

Blazars are characterized by relativistic jets that are closely aligned with our line of sight. This results in relativistic beaming, making blazars among the most luminous extragalactic sources across the electromagnetic spectrum, from…

High Energy Astrophysical Phenomena · Physics 2025-07-14 Stamatios Ilias Stathopoulos , Maria Petropoulou

We conducted an analysis of gamma-ray variability in a large sample of jetted active galactic nuclei (AGNs) by utilizing archival Fermi-LAT light curves and applying damped random walk modeling to obtain variability amplitude. Our primary…

High Energy Astrophysical Phenomena · Physics 2026-05-21 Yongyun Chen , Qiusheng Gu , Junhui Fan , Dingrong Xiong , Xiaoling Yu , Xiaogu Zhong , Xiaotong Guo , Nan Ding

High-redshift ($z>2$) blazars, with relativistic jets aligned toward us, probe the most powerful end of the active galactic nuclei (AGN) population. We aim at determining the black hole masses and mass accretion rates of high-$z$ blazars in…

High Energy Astrophysical Phenomena · Physics 2026-04-15 G. Kyriopoulos , M. Petropoulou , G. Vasilopoulos , D. Hatzidimitriou

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

We consider the 1.5 years Fermi Large Area Telescope light curves (E > 100 MeV) of the flat spectrum radio quasars 3C 454.3 and PKS 1510-089, which show high activity in this period of time. We characterise the duty cycle of the source by…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 F. Tavecchio , G. Ghisellini , G. Bonnoli , G. Ghirlanda

Before the launch of the Fermi Gamma-ray Space Telescope satellite only two classes of active galactic nuclei (AGN) were known to generate relativistic jets and thus to emit up to the $\gamma$-ray energy range: blazars and radio galaxies,…

High Energy Astrophysical Phenomena · Physics 2019-11-12 Filippo D'Ammando

The Broad Line Region of Active Galactic Nuclei is characterized by broad Balmer emission lines in their optical spectra. The broad Balmer emission lines are found to be asymmetric, some blue sided and others red sided in their asymmetry.…

Astrophysics of Galaxies · Physics 2014-09-23 Cosmos Dumba

Within the blazar population, hard X-ray selected objects are of particular interest as they tend to lie at each end of the blazar sequence. In particular, flat spectrum radio quasars located at high redshifts display the most powerful…

High Energy Astrophysical Phenomena · Physics 2013-02-12 Loredana Bassani , M. Molina , R. Landi , A. Malizia , A. J. Bird , A. Bazzano , P. Ubertini

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 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 search through $\gamma$-ray data obtained with the Large Area Telescope (LAT) onboard the Fermi Gamma-Ray Space Telescope and find 24 blazars (or candidates) that have a single clear flare event in their 9.5 year long-term light curves.…

High Energy Astrophysical Phenomena · Physics 2020-01-08 Gege Wang , Zhongxiang Wang , Liang Chen , Jianeng Zhou , Yi Xing

The impact of the Fermi Gamma-ray Space Telescope on blazar research is reviewed. This includes a brief description of the Fermi Large Area Telescope, a summary of the various classes of extragalactic sources found in the First Large Area…

High Energy Astrophysical Phenomena · Physics 2019-08-13 Charles D. Dermer

We present the results of extensive multi-frequency monitoring of the radio galaxy 3C 111 between 2004 and 2010 at X-ray (2.4--10 keV), optical (R band), and radio (14.5, 37, and 230 GHz) wave bands, as well as multi-epoch imaging with the…

Theoretical models for the production of relativistic jets from active galactic nuclei predict that jet power arises from the spin and mass of the central black hole, as well as the magnetic field near the event horizon. The physical…

High Energy Astrophysical Phenomena · Physics 2015-06-23 G. Ghisellini , F. Tavecchio , L. Maraschi , A. Celotti , T. Sbarrato

We study spectral properties of the brightest gamma-ray blazar 3C454.3 using 138 weeks of observations by the Fermi Gamma-ray Space Telescope (Fermi). We probe the behaviour of the source as a function of time at different brightness…

High Energy Astrophysical Phenomena · Physics 2012-01-09 Boris E. Stern , Juri Poutanen

Ever since the discovery by the Fermi mission that active galactic nuclei (AGN) produce copious amounts of high-energy emission, its origin has remained elusive. Using high-frequency radio interferometry (VLBI) polarization imaging, we…

High Energy Astrophysical Phenomena · Physics 2018-05-15 B. Rani , S. G. Jorstad , A. P. Marscher

We observed with the NuSTAR satellite 3 blazars at z>2, detected in gamma-rays by Fermi/LAT and in the soft X-rays, but not yet observed above 10 keV. The flux and slope of their X-ray continuum, together with Fermi/LAT data allows us to…

High Energy Astrophysical Phenomena · Physics 2019-07-10 G. Ghisellini , M. L. Perri , G. Costamante , G. Tagliaferri , T. Sbarrato , S. Campitiello , G. Madejski , F. Tavecchio , G. Ghirlanda