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Related papers: Surveys and the Blazar Parameter Space

200 papers

We present the results of nine years of the blazar observing programme at the RATAN-600 radio telescope (2005-2014). The data were obtained at six frequency bands (1.1, 2.3, 4.8, 7.7, 11.2, 21.7 GHz) for 290 blazars, mostly BL Lacs. In…

Astrophysics of Galaxies · Physics 2017-07-26 M. Mingaliev , Yu. Sotnikova , T. Mufakharov , E. Nieppola , M. Tornikoski , J. Tammi , A. Lahteenmaki , R. Udovitskiy , A. Erkenov

Blazars are a highly-variable, radio-loud subclass of active galactic nuclei (AGN). In order to better understand such objects we must be able to easily identify candidate blazars from the growing population of unidentified sources. Working…

High Energy Astrophysical Phenomena · Physics 2015-06-16 Philip S. Cowperthwaite , F. Massaro , R. D'Abrusco , A. Paggi , G. Tosti , Howard A. Smith

The infrared properties of blazars can be studied from the statistical point of view with the help of sky surveys, like that provided by the Wide-field Infrared Survey Explorer (WISE) and the Two Micron All Sky Survey (2MASS). However,…

We propose a scenario where blazars are classified as flat-spectrum radio quasars (FSRQs), BL Lacs, low synchrotron, or high synchrotron peaked objects according to a varying mix of the Doppler boosted radiation from the jet, the emission…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 P. Giommi , P. Padovani , G. Polenta , S. Turriziani , V. D'Elia , S. Piranomonte

Since 2002, the number of detected blazars at E_\gamma > 100 GeV has more than doubled. I study all currently known BL Lac-type objects with published energy spectra. Their intrinsic energy spectra are reconstructed by removing…

Astrophysics · Physics 2009-01-08 Robert Wagner

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 describe a uniform all-sky survey of bright blazars, selected primarily by their flat radio spectra, that is designed to provide a large catalog of likely gamma-ray AGN. The defined sample has 1625 targets with radio and X-ray properties…

Blazars are highly variable, radio-loud active galactic nuclei with jets oriented at a small angle to the line of sight. The observed emission of these sources covers the whole electromagnetic spectrum from radio frequencies up to the high…

High Energy Astrophysical Phenomena · Physics 2016-04-20 Alicja Wierzcholska

To investigate the poorly constrained sub-mm counts and spectral properties of blazars we searched for these in the Herschel-ATLAS (H-ATLAS) science demostration phase (SDP) survey catalog. We cross-matched 500$\mu$m sources brighter than…

We identify 3,113 highly variable objects in 7,200 square degrees of the Palomar-QUEST Survey, which each varied by more than 0.4 magnitudes simultaneously in two broadband optical filters on timescales from hours to roughly 3.5 years. The…

We have undertaken a survey of archived, pointed ROSAT PSPC data for blazars by correlating the ROSAT WGACAT database with several publicly available radio catalogs, restricting our candidate list to serendipitous flat radio spectrum…

The aim of this white paper is to discuss the observing strategies for the LSST Wide-Fast-Deep that would improve the study of blazars (emission variability, census, environment) and Fast Radio Bursts (FRBs). For blazars, these include the…

Instrumentation and Methods for Astrophysics · Physics 2018-12-10 C. M. Raiteri , M. I. Carnerero , B. Balmaverde , F. D'Ammando , C. Righi , A. Possenti , E. Pian , A. Capetti , M. Villata , M. Giroletti , P. Romano , A. Stamerra , F. Tavecchio , S. Vercellone

Our knowledge of the blazar surface densities and luminosity functions, which are fundamental parameters, relies still on samples at relatively high flux limits. As a result, our understanding of this rare class of active galactic nuclei is…

Astrophysics · Physics 2011-02-11 P. Padovani , P. Giommi , H. Landt , E. S. Perlman

We have considered all blazars observed in the X-ray band and for which the slope of the X-ray spectrum is available. We have collected 421 spectra of 268 blazars, including 12 archival unpublished ASCA spectra of 7 blazars whose analysisis…

Astrophysics · Physics 2009-11-06 D. Donato , G. Ghisellini , G. Tagliaferri , G. Fossati

With their rapid, violent variability and broad featureless continuum emission, blazars have puzzled astronomers for over two decades. Today blazars represent the only extragalactic objects detected in high-energy gamma-rays. Their spectral…

Astrophysics · Physics 2009-10-31 Eric S. Perlman

Surveys at mm wavelengths emphasize rare classes of extragalactic radio sources characterized by spectra keeping flat or inverted up to high frequencies (such as blazars, GPS sources, advection dominated sources, or even gamma-ray burst…

We carried out multi-color optical monitoring of a sample of ten blazars from 2005 to 2011. The sample contains 3 LBLs, 2 IBLs, 4 HBLs, and 1 FSRQ. Our monitoring focused on the long-term variability and the sample included nine BL Lac…

Astrophysics of Galaxies · Physics 2018-08-08 Nankun Meng , Xiaoyuan Zhang , Jianghua Wu , Jun Ma , Xu Zhou

We compiled the radio, optical, and X-ray data of blazars from the Sloan Digital Sky Survey (SDSS) database, and presented the distribution of luminosities and broad band spectral indices. The distribution of luminosities shows that the…

High Energy Astrophysical Phenomena · Physics 2015-03-20 Huaizhen Li , Luoen Chen , Yunguo Jiang , Tingfeng Yi

Utilizing the latest and the most sensitive radio and optical catalogs, we completed a new blazar candidate catalog, Blazar Radio and Optical Survey (BROS), which includes 88,211 sources located at declination $\delta > -40^{\circ}$ and…

High Energy Astrophysical Phenomena · Physics 2020-08-04 Ryosuke Itoh , Yousuke Utsumi , Yoshiyuki Inoue , Kouji Ohta , Akihiro Doi , Tomoki Morokuma , Koji S. Kawabata , Yasuyuki T. Tanaka

Blazars are a kind of active galactic nuclei (AGN) in which a relativistic jet is considered to be directed along the line of sight. They are characterized by strong and rapid variability of the flux and high polarization. We performed a…

High Energy Astrophysical Phenomena · Physics 2009-12-21 Y. Ikejiri , M. Uemura , M. Sasada , K. Sakimoto , R. Ito , M. Yamanaka , A. Arai , Y. Fukazawa , T. Ohsugi , K. S. Kawabata