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arXiv · 1207.5945

The nature of the intra-night optical variability in blazars

R. Bachev·E. Semkov·A. Strigachev·Alok C. Gupta·Haritma Gaur·B. Mihov·S. Boeva·L. Slavcheva-Mihova
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Abstract

In this paper we present results of a short-term optical monitoring of 13 blazars. The objects were monitored mostly in the R-band for a total of ~ 160 hours between 2006 and 2011. We study the nature of the short-term variations and show that most of them could be described as slow, smooth, and (almost) linear changes of up to ~ 0.1 mag/hour, but many objects show no short-term variations at all. In fact, we found only ~ 2 per cent chance to observe variability of more than 0.1 mag/hour for the sample we observed. Hints for quasi-periodic oscillations at very low amplitude levels are also found for some objects. We briefly discuss some of the possible mechanisms to generate the intra-night variability and the quasi-periodic oscillations.

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R. Bachev, E. Semkov, A. Strigachev, Alok C. Gupta, Haritma Gaur, B. Mihov, S. Boeva, L. Slavcheva-Mihova. 2012-07-25. The nature of the intra-night optical variability in blazars. https://doi.org/10.1111/j.1365-2966.2012.21310.x

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