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arXiv · 1012.2980

Fermi-LAT observations of the exceptional gamma-ray outbursts of 3C 273 in September 2009

A. A. Abdo et al.
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Abstract

We present the light curves and spectral data of two exceptionally luminous gamma-ray outburts observed by the Large Area Telescope (LAT) experiment on board Fermi Gamma-ray Space Telescope from 3C 273 in September 2009. During these flares, having a duration of a few days, the source reached its highest gamma-ray flux ever measured. This allowed us to study in some details their spectral and temporal structures. The rise and decay are asymmetric on timescales of 6 hours, and the spectral index was significantly harder during the flares than during the preceding 11 months. We also found that short, very intense flares put out the same time-integrated energy as long, less intense flares like that observed in August 2009.

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A. A. Abdo et al.. 2010-12-14. Fermi-LAT observations of the exceptional gamma-ray outbursts of 3C 273 in September 2009. https://doi.org/10.1088/2041-8205%2F714%2F1%2Fl73

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