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Related papers: S5 1803+78 revisited

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We have observed S4 0954+658 in the BVRI bands in 2001, and in the BI bands in 2002. The observations resulted in almost evenly sampled light curves, 3-8 hours long, with an average sampling interval of ~5-15 min. Because of the dense…

Astrophysics · Physics 2009-11-10 I. E. Papadakis , V. Samaritakis , P. Boumis , J. Papamastorakis

We report the results from our study of the blazar S5 1803+784 carried out using the quasi-simultaneous $B$, $V$, $R$, and $I$ observations from May 2020 to July 2021 on 122 nights. Our observing campaign detected the historically bright…

High Energy Astrophysical Phenomena · Physics 2022-07-20 A. Agarwal , Ashwani Pandey , Aykut Özdönmez , Ergün Ege , Avik Kumar Das , Volkan Karakulak

We present the results of an extensive analysis of the optical, ultraviolet, X-ray and $\gamma$-ray data collected from the observations of the BL Lac objects prototype BL Lacertae carried out over a period of nearly 13 years, between…

High Energy Astrophysical Phenomena · Physics 2022-04-20 N. Sahakyan , P. Giommi

We monitored the BL Lac object S5 0716+714 in the optical band during October 2008, December 2008 and February 2009 with a best temporal resolution of about 5 minutes in the BVRI bands. Four fast flares were observed with amplitudes ranging…

Astrophysics of Galaxies · Physics 2014-11-20 H. Poon , J. H. Fan , J. N. Fu

The optical (BVRI) and radio (8.4 GHz) light curves of S5 1803+784 on a time span of nearly 6 years are presented and discussed. The optical light curve showed an overall variation greater than 3 mag, and the largest changes occured in…

Astrophysics · Physics 2009-11-07 R. Nesci , E. Massaro , M. Maesano , F. Montagni , S. Sclavi , T. Venturi , D. Dallacasa , F. D'Alessio

Using the 1.56m telescope at the Shanghai Observatory (ShAO), China, we monitored two sources, BL Lac object S5 0716+714 and Flat Spectrum Radio Quasar (FSRQ) 3C 273. For S5 0716+714, we report 4969 sets of CCD (Charge-coupled Device)…

Astrophysics of Galaxies · Physics 2017-09-06 Yu-Hai Yuan , Jun-hui Fan , Jun Tao , Bo-Chen Qian , Denise Costantin , Hu-Bing Xiao , Zhi-Yuan Pei , Chao Lin

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 present the observational results of multi-colour optical monitoring of eight red blazars from 2003 September to 2004 February. The aim of our monitoring is to investigate the spectral variability as well as the flux variations at short…

Astrophysics · Physics 2009-11-11 Minfeng Gu , C. -U. Lee , Soojong Pak , H. S. Yim , A. B. Fletcher

Optical monitoring of S5 0716+714 was performed with a 60/90 Schmidt telescope in 2003 November and December and 2004 January for studying the variability of the object on short timescales. Due to the high brightness of the source we could…

Astrophysics · Physics 2009-11-10 Jianghua Wu , Bo Peng , Xu Zhou , Jun Ma , Zhaoji Jiang , Jiansheng Chen

The GeV observations by Fermi-LAT give us the opportunity to characterize the high-energy emission (100 MeV - 300 GeV) variability properties of the BL Lac object S5 0716+714. In this study, we performed flux and spectral analysis of more…

High Energy Astrophysical Phenomena · Physics 2015-06-15 B. Rani , T. P. Krichbaum , B. Lott , L. Fuhrmann , J. A. Zensus

We continuously monitored the blazar S5 0716+714 in the optical $g$, $r$ and $i$ bands from Nov. 10, 2017 to Jun. 06, 2019. The total number of observations is 201 nights including 26973 data points. This is a very large quasi-simultaneous…

High Energy Astrophysical Phenomena · Physics 2020-04-01 Dingrong Xiong , Jinming Bai , Junhui Fan , Dahai Yan , Minfeng Gu , Xuliang Fan , Jirong Mao , Nan Ding , Rui Xue , Weimin Yi

The radio, optical, and $\gamma$-ray light curves of the blazar S5 1803+784, from the beginning of the {\it Fermi} Large Area Telescope (LAT) mission in August 2008 until December 2018, are presented. The aim of this work is to look for…

High Energy Astrophysical Phenomena · Physics 2021-03-03 R. Nesci , S. Cutini , C. Stanghellini , F. Martinelli , A. Maselli , V. M. Lipunov , V. Kornilov , R. R. Lopez , A. Siviero , M. Giroletti , M. Orienti

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 the results of a series of radio, optical, X-ray and gamma-ray observations of the BL Lac object S50716+714 carried out between April 2007 and January 2011. The multi-frequency observations were obtained using several ground and…

We report results from a 1 week multi-wavelength campaign to monitor the BL Lac object S5 0716+714 (on December 9-16, 2009). In the radio bands the source shows rapid (~ (0.5-1.5) day) intra-day variability with peak amplitudes of up to ~…

BL Lac has been observed during the outburst occurred in the 1997 summer (Noble et al. 1997; Bloom et al. 1997) in three optical bands (BVI), with the aim of studying the intranight colour variations on very short timescales. Due to the…

Astrophysics · Physics 2007-05-23 R. Speziali , G. Natali

We examine the 2008-2016 $\gamma$-ray and optical light curves of three bright BL Lac objects, 0716+714, MRK 421, BL Lac, which exhibit large structured variability. We searched for periodicities by using a fully Bayesian approach. For two…

We have observed S5 2007+777 and 3C371 in the B and I bands for 13 and 8 nights, respectively, during various observing runs in 2001, 2002 and 2004. The observations resulted in almost evenly sampled light curves, 6-9 hours long. We do not…

We address the topic of the Intra-Night Optical Variability of the BL Lac object S5 0716+714. To this purpose a long term observational campaign was performed, from 1996 to 2003, which allowed the collection of a very large data set,…

Astrophysics · Physics 2009-11-11 F. Montagni , A. Maselli , E. Massaro , R. Nesci , S. Sclavi , M. Maesano

We present a detailed temporal and spectral study of the blazar 3C\,279 using multi-wavelength observations from Swift-XRT, Swift-UVOT and Fermi-LAT during a flare in 2018 January. The temporal analysis of $\gamma$-ray light curve indicates…

High Energy Astrophysical Phenomena · Physics 2021-06-03 Zahir Shah , V. Jithesh , S. Sahayanathan , Ranjeev Misra , Naseer Iqbal
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