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Related papers: The Fermi blazars divide

200 papers

The LAT instrument, onboard the Fermi satellite, in its first three months of operation detected more than 100 blazars at more than the 10 sigma level. This is already a great improvement with respect to its predecessor, the instrument…

Cosmology and Nongalactic Astrophysics · Physics 2009-12-18 G. Ghisellini

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

We study the relation between the mass accretion rate, the jet power, and the black hole mass of blazars. To this aim, we make use of the Sloan Digital Sky Survey (SDSS) and the 11 months catalog of blazars detected at energies larger than…

High Energy Astrophysical Phenomena · Physics 2012-05-18 T. Sbarrato , G. Ghisellini , L. Maraschi , M. Colpi

We have recently proposed a new simplified scenario where blazars are classified as flat-spectrum radio quasars (FSRQs) or BL Lacs according to the prescriptions of unified schemes, and to a varying combination of Doppler boosted radiation…

High Energy Astrophysical Phenomena · Physics 2015-06-15 P. Giommi , P. Padovani , G. Polenta

We present long term optical and near infrared flux variability analysis of 37 blazars detected in the $\gamma$-ray band by the {\it Fermi Gamma-Ray Space Telescope}. Among them, 30 are flat spectrum radio quasars (FSRQs) and 7 are BL Lac…

High Energy Astrophysical Phenomena · Physics 2020-08-28 P. Z. Safna , C. S. Stalin , Suvendu Rakshit , Blesson Mathew

The $Fermi$ blazar observations show a strong correlation between $\gamma$-ray luminosities and spectral indices. BL Lac objects are less luminous with harder spectra than flat-spectrum radio quasars (FSRQs). Interestingly FSRQs are evident…

High Energy Astrophysical Phenomena · Physics 2019-04-24 Tushar Mondal , Banibrata Mukhopadhyay

With the release of the first year Fermi catalogue, the number of blazars detected above 100 MeV lying at high redshift has been largely increased. There are 28 blazars at z>2 in the "clean" sample. All of them are Flat Spectrum Radio…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 G. Ghisellini , G. Tagliaferri , L. Foschini , G. Ghirlanda , F. Tavecchio , R. Della Ceca , F. Haardt , M. Volonteri , N. Gehrels

We present statistical analyses of a large homogenous data sample of Fermi-detected blazars thoroughly studied in order to reassess the relationship between flat-spectrum radio quasars (FSRQs) and subclasses of BL Lacertae objects (BL Lacs)…

High Energy Astrophysical Phenomena · Physics 2021-08-18 E. U. Iyida , F. C. Odo , A. E. Chukwude , A. A. Ubachukwu

We present the first measurement of the projected correlation function of 485 gamma-ray selected Blazars, divided in 175 BLLacertae (BL Lacs) and 310 Flat Spectrum Radio Quasars (FSRQs) detected in the 2-year all-sky survey by Fermi-Large…

Astrophysics of Galaxies · Physics 2015-06-23 Viola Allevato , Alexis Finoguenov , Nico Cappelluti

Many blazars detected by the Fermi satellite, observed spectroscopically in the optical, are line-less, and have been classified as BL Lac objects. Optical-UV photometry of nearly one hundred of them allowed to determine the redshift for a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 G. Ghisellini , F. Tavecchio , L. Foschini , T. Sbarrato , G. Ghirlanda , L. Maraschi

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

Using public \fermi LAT and \swift BAT observations, we constructed the first sample of blazars selected at both hard X-rays and gamma-rays. Studying its spectral properties, we find a luminosity dependence of the spectral slopes at both…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-22 R. M. Sambruna , D. Donato , M. Ajello , L. Maraschi , the GSFC BAT Team

We revisit the blazar sequence exploiting the complete, flux limited sample of blazars with known redshift detected by the Fermi satellite after 4 years of operations (the 3LAC sample). We divide the sources into gamma-ray luminosity bins,…

High Energy Astrophysical Phenomena · Physics 2017-05-31 G. Ghisellini , C. Righi , L. Costamante , F. Tavecchio

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

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 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 parsec-scale radio properties of 232 active galactic nuclei (AGNs), most of which are blazars, detected by the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope have been observed contemporaneously by the Very Long…

High Energy Astrophysical Phenomena · Physics 2015-06-11 J. D. Linford , G. B. Taylor , F. K. Schinzel

The Fermi Large Area Telescope (LAT) has detected more than 5000 gamma-ray sources in its first 8 years of operation. More than 3000 of them are blazars. About 60 per cent of the Fermi-LAT blazars are classified as BL Lacertae objects (BL…

High Energy Astrophysical Phenomena · Physics 2020-06-22 Miloš Kovačević , Graziano Chiaro , Sara Cutini , Gino Tosti

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 exact location of the gamma-ray emitting region in blazars is still controversial. In order to attack this problem we present first results of a cross-correlation analysis between radio (11 cm to 0.8 mm wavelength, F-GAMMA program) and…

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