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We have monitored the BL Lacertae object S5 0716+714 in the optical bands during 2012 January and February with long time spans on intraday timescales ($>$5 hr) and high time resolutions. During this monitoring period, the object shows…

High Energy Astrophysical Phenomena · Physics 2017-07-19 Shanwei Hong , Dingrong Xiong , Jinming Bai

We present the results of our optical monitoring of the BL Lac object S5 0716+714 on seven nights in 2006 December. The monitoring was carried out simultaneously at three optical wavelengths with a novel photometric system. The object did…

High Energy Astrophysical Phenomena · Physics 2015-06-04 Jianghua Wu , Markus Boettcher , Xu Zhou , Xiangtao He , Jun Ma , Zhaoji Jiang

We perform quasi-simultaneous optical multi-band monitoring of BL Lac object S5 0716+714 on seven nights from 2013 to 2016. Intra-day variability (IDV) is found on all seven nights. The source was faintest on JD 2456322 with 14.15 mags and…

Astrophysics of Galaxies · Physics 2018-06-22 Xiaoyuan Zhang , Jianghua Wu , Nankun Meng

We monitored BL Lacertae simultaneously in the optical B, V, R and I bands for 13 nights during the period 2012-2016. The variations were well correlated in all bands and the source showed significant intraday variability (IDV). We also…

Astrophysics of Galaxies · Physics 2017-06-23 Nankun Meng , Jianghua Wu , James R. Webb , Xiaoyuan Zhang , Yan Dai

We have monitored the BL Lacertae object S5 0716+714 simultaneously in the B, R and I bands on three nights in November 2014. The average time resolution is quite high (73s, 34s, 58s for the filters B, R and I), which can help us trace the…

Astrophysics of Galaxies · Physics 2016-01-27 Zhongyi Man , Xiaoyuan Zhang , Jianghua Wu , Qirong Yuan

In this work, we present the results of our multi-band microvariability study of the famous blazar BL Lac. We performed microvariablity observations of the source in the optical VRI bands for 4 nights in the year 2016. We studied the…

High Energy Astrophysical Phenomena · Physics 2017-11-27 Gopal Bhatta , James R. Webb

We report results of multiband optical monitoring of two well known blazars, S5 0716+714 and BL Lacertae, carried out in 1996 and 2000-01 with an aim to study optical variations on time scales from minutes to hours and longer.The light…

Astrophysics · Physics 2007-05-23 C. S. Stalin , Gopal-Krishna , Ram Sagar , Paul J. Wiita , V. Mohan , A. K. Pandey

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

We have observed BL Lacertae in the B, R and I bands for 2 nights in July, 1999, and 3 nights in July, 2001. The observations resulted in almost evenly sampled light curves, with an average sampling interval of ~5 min. The source is…

Astrophysics · Physics 2009-11-07 I. E. Papadakis , P. Boumis , V. Samaritakis , J. Papamastorakis

We monitored BL Lacertae frequently during 2014 - 2016 when it was generally in a high state. We searched for intra-day variability for 43 nights using quasi-simultaneous measurements in the B, V, R, and I bands (totaling 143 light curves);…

High Energy Astrophysical Phenomena · Physics 2017-12-20 Haritma Gaur , Alok C. Gupta , R. Bachev , A. Strigachev , E. Semkov , Paul J. Wiita , M. F. Gu , S. Ibryamov

We have monitored the BL Lac object S5 0716+714 in five intermediate optical wavebands from 2004 September to 2011 April. Here we present the data that include 8661 measurements which represents one of the largest databases obtained for an…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Yan Dai , Jianghua Wu , Zong-Hong Zhu , Xu Zhou , Jun Ma , Qirong Yuan , Lingzhi Wang

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 analyzed the multi-band optical behaviour of the BL Lacertae object, S5 0716+714, during its outburst state from 2014 November - 2015 March. We took data on 23 nights at three observatories, one in India and two in Bulgaria, making…

High Energy Astrophysical Phenomena · Physics 2017-12-20 Aditi Agarwal , Alok C. Gupta , R. Bachev , A. Strigachev , E. Semkov , Paul J. Wiita , J. H. Fan , U. S. Pandey , S. Boeva , B. Spassov

We present the results of extensive multi-band intra-night optical monitoring of BL Lacertae during 2010--2012. BL Lacertae was very active in this period and showed intense variability in almost all wavelengths. We extensively observed it…

We report rapid optical variability for the blazar S5 0716+71 during 2010 March 08-10 & 19-20 in the CCD observations made from Mt.Abu Infrared Observatory. The light curves are constructed for the duration longer than 3-hours each night,…

High Energy Astrophysical Phenomena · Physics 2011-05-04 Sunil Chandra , K. S. Baliyan , S. Ganesh , U. C. Joshi

We monitored BL Lacertae in the B, V, R and I bands for 14 nights during the period of 2016-2018. The source showed significant intraday variability on 12 nights. We performed colour-magnitude analysis and found that the source exhibited…

Astrophysics of Galaxies · Physics 2021-12-08 Tian Li , Jianghua Wu , Nankun Meng , Yan Dai , Xiaoyuan Zhang

With an aim to explore optical variability at diverse timescales in BL Lac source S5 0716+714, it was observed for 46 nights during 2013 January 14 to 2015 June 01 when it underwent two major outbursts. The observations were made using the…

Astrophysics of Galaxies · Physics 2018-09-26 Navpreet Kaur , Kiran S. Baliyan , S. Chandra , Sameer , S. Ganesh

We present photometric observations of the BL Lacertae object S5 0716+714 with a temporal resolution of 120 s in the Sloan i' and r' bands. These observations were conducted using the Comet Search Program telescope at Xingming Observatory…

Astrophysics of Galaxies · Physics 2025-03-17 Huai-Zhen Li , Di-Fu Guo , Long-Hua Qin , Fen Liu , Hong-Tao Liu , Ting-Feng Yi , Quan-Gui Gao , Shi-Feng Huang , Xing Gao , Xu Chen

We monitored BL Lacertae for 13 nights in optical B, V, R, and I bands during October and November 2014 including quasi-simultaneous observations in V and R bands using two optical telescopes in India. We have studied multi-band optical…

Astrophysics of Galaxies · Physics 2015-06-02 Aditi Agarwal , Alok C. Gupta

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
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