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Related papers: Optical Intra-day Variability in Blazars

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We present results of our intra-night optical flux monitoring observations of S5 0716+714 done simultaneously in gRI filters. The observations were done using Multicolor Imaging Telescopes for Survey and Monstrous Explosions (MITSuME)…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 C. S. Stalin , K. S. Kawabata , M. Uemura , M. Yoshida , N. Kawai , K. Yanagisawa , Y. Shimizu , D. Kuroda , S. Nagayama , H. Toda

We developed a method to separate a long-term trend from observed temporal variations of polarization in blazars using a Bayesian approach. The temporal variation of the polarization vector is apparently erratic in most blazars, while…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Makoto Uemura , Koji S. Kawabata , Mahito Sasada , Yuki Ikejiri , Kiyoshi Sakimoto , Ryosuke Itoh , Masayuki Yamanaka , Takashi Ohsugi , Shuji Sato , Masaru Kino

About twenty years of radio observations in five bands (from 4.8 to 37 GHz) of the BL Lac object GC 0109+224 (S2 0109+22, RGB J0112+227), are presented and analysed together with the optical data. Over the past ten years this blazar has…

Astrophysics · Physics 2016-08-16 Stefano Ciprini , Gino Tosti , Harri Teräsranta , Hugh D. Aller

We present a study of the intraday variability behaviour of a complete sample of radio-selected BL Lac objects taken from the 1 Jy catalogue. In 28 out of 34 BL Lac objects (82\%) we detected intraday variability. 7 objects were observed…

Astrophysics · Physics 2016-08-30 Jochen Heidt , Stefan J. Wagner

We present an optical-to-radio study of the BL Lac object S4 0954+658 observations during 1998-2023. The measurements were obtained with the SAO RAS Zeiss-1000 1-m and AS-500/2 0.5-m telescopes in 2003-2023, with the RATAN-600 radio…

The long-term optical, X-ray and $\gamma$-ray data of blazar 3C 279 have been compiled from $Swift$-XRT, $RXTE$ PCA, $Fermi$-LAT, SMARTS and literature. The source exhibits strong variability on long time scales. Since 1980s to now, the…

High Energy Astrophysical Phenomena · Physics 2021-11-03 Bing-Kai Zhang , Min Jin , Xiao-Yun Zhao , Li Zhang , Ben-Zhong Dai

We report the results of quasi-simultaneous two filter optical monitoring of two high-energy peaked blazars, 1ES 1959+650 and 1ES 2344+514, to search for microvariability and short-term variability (STV). We carried out optical photometric…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Haritma Gaur , Alok C. Gupta , A. Strigachev , R. Bachev , E. Semkov , Paul J. Wiita , S. Peneva , S. Boeva , N. Kacharov , B. Mihov , E. Ovcharov

Here we present the first optical photometric monitoring results of a sample of twelve newly discovered blazars from the ICRF - Gaia CRF astrometric link. The observations were performed from April 2013 until August 2019 using eight…

High Energy Astrophysical Phenomena · Physics 2023-04-26 Miljana D. Jovanovic , Goran Damljanovic , Francois Taris , Alok C. Gupta , Gopal Bhatta

For 3 radio-loud $\gamma$-ray detected Narrow-Line Seyfert 1 ($\gamma$-ray NLSy1) galaxies, we report optical variability on intra-night and/or week-like time scales, based on five $\geq$ 3 hours long monitoring sessions for each galaxy.…

Astrophysics of Galaxies · Physics 2018-12-12 Vineet Ojha , Gopal-Krishna , Hum Chand

The BL Lac object S5 0716+71 was target of a coordinated and global multi-frequency campaign to search for rapid and correlated variability and signatures of the inverse-Compton catastrophe. Here we present first results obtained from a…

We have obtained simultaneous and continuous photo-polarization observations of the blazar BL Lacertae in optical and near-infrared (NIR) bands during a historical outburst from 2020 to 2021. In total, fourteen nights of observations were…

At the end of March 2004, the blazar S5 0716+714 underwent an optical outburst that prompted for quasi-simultaneous target-of-opportunity observations with the INTEGRAL and XMM-Newton satellites. In this paper, we report the results of the…

Flaring episodes in blazars represent one of the most violent processes observed in extra-galactic objects. Studies of such events shed light on the energetics of the physical processes occurring in the innermost regions of blazars, which…

Studying the periodic flux-variation behavior of blazars is vital for probing supermassive black hole binaries and the kinematics of relativistic jets. In this work, we report the detection of the multi-band possible periodic variations of…

High Energy Astrophysical Phenomena · Physics 2024-11-12 Guowei Ren , Mouyuan Sun , Nan Ding , Xing Yang , Zhixiang Zhang

Very recently, J 1128+5925 was found to show strong intraday variability at radio wavelengths and may be a new source with annual modulation of the timescale of its radio variability. Therefore, its radio variability can be best explained…

Astrophysics · Physics 2008-11-26 Jianghua Wu , Xu Zhou , Jun Ma , Zhenyu Wu , Zhaoji Jiang , Jiansheng Chen

In Spring 2005, the blazar 3C454.3 underwent a dramatic outburst at all wavelengths from mm to X-rays. This prompted INTEGRAL observations, accomplished in 15-18 May 2005. The source was detected by the INTEGRAL instruments from 3 to 200…

Astrophysics · Physics 2009-11-11 Elena Pian , Luigi Foschini , Volker Beckmann

Using newly released data from the Wide-field Infrared Survey Explorer, we report the discovery of rapid infrared variability in three radio-loud narrow-line Seyfert 1 galaxies (NLS1s) selected from the 23 sources in the sample of Yuan et…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Ning Jiang , Hong-Yan Zhou , Luis C. Ho , Weimin Yuan , Ting-Gui Wang , Xiao-Bo Dong , Peng Jiang , Tuo Ji , Qiguo Tian

Context. The international whole earth blazar telescope (WEBT) consortium planned and carried out three days of intensive micro-variability observations of S5 0716+714 from February 22, 2009 to February 25, 2009. This object was chosen due…

The blazars 3C 454.3, PKS 0537-441 and PKS 2155-304 are traditionally known to be among the most active sources of this class. They emit at all frequencies, up to the gamma-rays, and are good probes of multiwavelength nuclear variability.…

Astrophysics · Physics 2007-07-25 Elena Pian , Luigi Foschini , Gabriele Ghisellini

The gamma-ray emission of blazar jets shows a pronounced variability and this feature provides limits to the size and to the speed of the emitting region. We study the gamma-ray variability of bright blazars using data from the first 18…

High Energy Astrophysical Phenomena · Physics 2015-05-28 T. Sbarrato , L. Foschini , G. Ghisellini , F. Tavecchio