Related papers: Color Behavior Of BL Lacertae Object OJ 287 During…
We present the results of our optical monitoring of the BL Lacertae object OJ 287 during the first half of 2005. The source did not show large-amplitude variations during this period and was in a relatively quiescent state. A possible…
OJ287 is a BL Lac object at redshift z=0.306 that has shown double-peaked bursts at regular intervals of ~12 yr during the last ~ 40 yr. Due to this behavior, it has been suggested that OJ287 might host a close supermassive binary black…
(Abridged) OJ287 is a BL Lac object that has shown double-peaked bursts at regular intervals of ~12 yr during the last ~40 yr. We analyse optical photopolarimetric monitoring data from 2005-2009, during which the latest double-peaked…
Context. The blazar OJ 287 has been proposed as a binary black hole system based on its periodic optical outburst. Among blazars with parsec scale jets, the black hole binary systems are very rare and hence this source is very interesting…
We present recent optical photometric observations of the blazar OJ 287 taken during September 2015 -- May 2016. Our intense observations of the blazar started in November 2015 and continued until May 2016 and included detection of the…
We present analyses of Suzaku XIS light curves and spectra of the BL Lac object OJ 287 with observations positioned primarily around proposed recurrent optical outbursts. The first two observations were performed in 2007 April 10 - 13…
The BL Lacertae (BL Lac) object OJ 287 is one of the most dynamic blazars across the directly accessible observational windows: spectral, timing, polarization, and imaging. Apart from behaviors considered characteristics of blazars, it…
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…
Recent intensive observations of the BL Lac object OJ 287 raise a lot of questions on the models of binary black holes, processing jets, rotating helical jets and thermal instability of slim accretion disks. After carefully analyzing their…
Recent analysis of the long term radio lightcurve of the extremely variable BL Lacertae object AO 0235+16 by Raiteri et al. (2001) have revealed the presence of recurrent outbursts in this source with a period of ~ 5.7 +/- 0.5 yr.…
The light curves of optical outbursts observed in blazar OJ287 during 1983-2015 are analyzed and model-simulated to investigate the nature of its optical radiation. It is shown that the December/2015 outburst has its multi-wavelength…
BL Lacertae had undergone a series of historical high flux activity over a year, from August 2020 in the optical to VHE $\gamma$-rays. In this paper, we report on optical flux and spectral variability of the first historical maxima outburst…
The BL Lacertae object OJ 287 (z = 0.306) has unique double-peaked optical outbursts every ~12 years, and it presents one of the best cases for a small-separation binary supermassive black hole (SMBH) system, with an extremely massive…
As a characteristic feature of generic blazars the polarization behavior of the quasi-periodic optical outbursts observed in OJ287 is investigated. The optical light-curves of the December/2015 outburst are also simulated in terms of the…
The light curve of the quasar OJ 287 extends from 1891 up today without major gaps. Here we summarize the results of the 2005 - 2010 observing campaign. The main results are the following: (1) The 2005 October optical outburst came at the…
The BL Lacertae object OJ 287 is a very unusual quasar producing a wobbling radio jet and some double-peaked optical outbursts with a possible period of about 12 yr for more than one century. This variability is widely explained by models…
OJ 287 is a bright blazar with century-long observations, and one of the strongest candidates to host a supermassive black hole binary. Its polarisation behaviour between 2015 and 2017 (MJD 57300-58000) contains several interesting events…
We present the results of a temporal and spectral study of the BL Lacertae object OJ 287 in optical, UV, and X-ray bands with observations performed by Swift satellite during September 2019--March 2020. In this period, the source showed…
We present observations of a major outburst at centimeter, millimeter, optical, X-ray, and gamma-ray wavelengths of the BL Lacertae object AO 0235+164. We analyze the timing of multi-waveband variations in the flux and linear polarization,…
We try to propose a tentative relativistic jet model for explaining the entire radio-optical phenomena observed in blazar OJ287, which has been observed quasi-periodically with a cycle of about 12yr in its optical light curve. We…