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Related papers: Blazar Optical Variability in the Palomar-QUEST Su…

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The long-term optical and infrared color variability of blazars has been investigated with the SMARTS monitoring data. The sample in this study consists of 49 flat spectrum radio quasars and 22 BL Lac objects. The fractional variability…

Astrophysics of Galaxies · Physics 2015-11-11 Bing-Kai Zhang , Xiao-Shan Zhou , Xiao-Yun Zhao , Ben-Zhong Dai

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

In this study, we analyze the $\sim 16$ yr Fermi-LAT data of 160 blazars consisting of 92 flat-spectrum radio quasars (FSRQs), 64 BL Lacertae type objects (BL Lacs), and 4 blazar candidates of unknown type objects (BCU), and exhibit their…

High Energy Astrophysical Phenomena · Physics 2025-01-22 Junhao Deng , Yunguo Jiang

We studied the optical variability of 241 BL Lacs and 83 flat-spectrum radio quasars (FSRQ) from the 4LAC catalog using data from the Tomo-e Gozen Northern Sky Transient Survey, with $\sim$ 50 epochs per blazar on average. We excluded…

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 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

Blazars can be divided into two subtypes, flat spectrum radio quasars (FSRQs) and BL Lac objects, which have been distinguished phenomenologically by the strength of their optical emission lines, while their physical nature and relationship…

High Energy Astrophysical Phenomena · Physics 2020-07-22 Makoto Uemura , Taisei Abe , Yurika Yamada , Shiro Ikeda

The ensemble variability properties of nearly 23,000 quasars are studied using the Palomar-QUEST Survey. The survey has covered 15,000 square degrees multiple times over 3.5 years using 7 optical filters, and has been calibrated…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-11 Anne Bauer , Charles Baltay , Paolo Coppi , Nancy Ellman , Jonathan Jerke , David Rabinowitz , Richard Scalzo

In this study, we conducted a systematic analysis of long-term Fermi-LAT \gamma-ray data for a sample of blazars, including FSRQs, BL\,Lacs, and BCUs, to investigate their $\gamma$-ray variability. We focused on light curves binned in 3-,…

We report the results of optical monitoring for a sample of 11 blazars including 10 BL Lacs and 1 Flat Spectrum Radio Quasar (FSRQ). We have measured the multiband optical flux and colour variations in these blazars on intra-day and…

High Energy Astrophysical Phenomena · Physics 2013-11-21 Haritma Gaur , Alok C. Gupta , A. Strigachev , R. Bachev , E. Semkov , Paul J. Wiita , S. Peneva , S. Boeva , L. Slavcheva-Mihova , B. Mihov , G. Latev , U. S. Pandey

We present a polarization variability analysis of a sample of 26 $\gamma$-ray blazars monitored by the Steward Observatory between 2008 and 2018 in the optical band. We investigate the properties and long-term variability of their optical…

We present results from four years of twice-weekly 15 GHz radio monitoring of about 1500 blazars with the Owens Valley Radio Observatory 40 m telescope. Using the intrinsic modulation index to measure variability amplitude, we find that,…

High Energy Astrophysical Phenomena · Physics 2014-01-16 Joseph L. Richards , Talvikki Hovatta , Walter Max-Moerbeck , Vasiliki Pavlidou , Timothy J. Pearson , Anthony C. S. Readhead

We present results from the first dedicated study in the time domain of the hard X-ray variability behavior of blazars on long timescales based on $\sim$13 years of continuous hard X-ray data in the 14-195 keV band. We use monthly-binned…

High Energy Astrophysical Phenomena · Physics 2023-10-10 Sergio Mundo , Richard Mushotzky

The colour behaviour of blazars is a subject of much debate. One argument is that the BL Lac objects show bluer-when-brighter chromatism while the flat-spectrum radio quasars (FSRQs) display redder-when-brighter trend. Base on a 3.5-year…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Jianghua Wu , Zhou Xu , Jun Ma , Zhaoji Jiang

Blazars are known to show periods of quiescence followed by outbursts visible throughout the electromagnetic spectrum. We present a novel maximum likelihood approach to capture this bimodal behavior by examining blazar radio variability in…

High Energy Astrophysical Phenomena · Physics 2017-03-30 I. Liodakis , V. Pavlidou , T. Hovatta , W. Max-Moerbeck , T. J. Pearson , J. L. Richards , A. C. S. Readhead

We present an in-depth and systematic variability study of a sample of 20 powerful blazars, including 12 BL Lacs and 8 flat spectrum radio quasars, applying various analysis tools such as flux distribution, symmetry analysis, and time…

High Energy Astrophysical Phenomena · Physics 2020-03-18 Gopal Bhatta , Niraj Dhital

Using data from the Wide-field Infrared Survey Explorer we studied the mid infrared 3.4 $\mu$m (W1-band) and 4.6 $\mu$m (W2-band) flux variability of $\gamma$-ray emitting blazars. Our sample consists of 460 flat spectrum radio quasars…

Astrophysics of Galaxies · Physics 2020-04-15 Ayesha Anjum , C. S. Stalin , Suvendu Rakshit , S. B. Gudennavar , Alok Durgapal

In an optical monitoring program to characterize the variability properties of blazar, we observed 10 sources from the Roma-BZCAT catalogue for 26 nights in V and R bands during October 2014 to June 2015 with two telescopes located in…

High Energy Astrophysical Phenomena · Physics 2021-12-08 Nibedita Kalita , Alok C. Gupta , Minfeng Gu

We use optical data from the Palomar Transient Factory (PTF) and the Catalina Real-Time Transient Survey (CRTS) to study the variability of gamma-ray detected and non-detected objects in a large population of active galactic nuclei (AGN)…

We present results of a variability study in the optical band of 44 newly identified blazar candidates behind the Magellanic Clouds. Our sample contains 27 flat spectrum radio quasars (FSRQs) and 17 BL Lacertae objects (BL Lacs). However,…

High Energy Astrophysical Phenomena · Physics 2019-11-11 Natalia Żywucka , Mariusz Tarnopolski , Markus Böttcher , Łukasz Stawarz , Volodymyr Marchenko
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