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arXiv · 1304.2878

Fermi LAT detection of extraordinary variability in the gamma-ray emission of the blazar PKS 1510-089

L. Foschini·G. Bonnoli·G. Ghisellini·G. Tagliaferri·F. Tavecchio·A. Stamerra
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Abstract

We have reanalyzed the giant outburst of the blazar PKS 1510-089 (z=0.36) that occurred on 2011 October-November. The gamma-ray flux in the 0.1-100 GeV energy range exceeded the value of 10^-5 ph/cm2/s for several days. The peak flux was reached on 2011 October 19, with a value of 4.4 x 10^-5 ph/cm2/s, which in turn corresponds to a luminosity of 2 x 10^49 erg/s. A very short timescale variability was measured. Particularly on 2011 October 18, the flux-doubling time was as short as 20 minutes. This is the shortest variability ever detected in the MeV-GeV energy band. We compared our analysis with two other outbursts observed in 2009 March and 2012 February-March, when the blazar was also detected by HESS and MAGIC to infer information about the emission at hundreds of GeV.

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L. Foschini, G. Bonnoli, G. Ghisellini, G. Tagliaferri, F. Tavecchio, A. Stamerra. 2013-06-18. Fermi LAT detection of extraordinary variability in the gamma-ray emission of the blazar PKS 1510-089. https://doi.org/10.1051/0004-6361%2F201321675

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