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arXiv · 1702.05335

Quasi-Periodicities at Year Time Scales in Blazars

Stefano Covino·Angela Sandrinelli·Aldo Treves
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Abstract

We examine the 2008-2016 gamma-ray and optical light curves of a number of bright Fermi blazars. In a fraction of them, the periodograms show possible evidence of quasi-periodicities related in the two bands. This coincidence strengthens their physical meaning. Comparing with results from the periodicity search of quasars, the presence of quasi-periodicities in blazars suggests that the basic condition for its observability is related to the relativistic jet in the observer direction, but the overall picture remains uncertain.

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Stefano Covino, Angela Sandrinelli, Aldo Treves. 2017-02-17. Quasi-Periodicities at Year Time Scales in Blazars. https://doi.org/10.1017/s174392131700237x

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