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arXiv · 1503.08226

The first gamma-ray detection of the narrow-line Seyfert 1 FBQS J1644+2619

F. D'Ammando·M. Orienti·J. Larsson·M. Giroletti
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Abstract

We report the discovery of gamma-ray emission from the narrow-line Seyfert 1 (NLSy1) galaxy FBQS J1644+2619 by the Large Area Telescope on board the Fermi satellite. The Third Fermi LAT Source catalogue reports an unidentified gamma-ray source, detected over the first four years of Fermi operation, 0.23 deg from the radio position of the NLSy1. Analysing 76 months of gamma-ray data (2008 August 4 - 2014 December 31) we are able to better constrain the localization of the gamma-ray source. The new position of the gamma-ray source is 0.05 deg from FBQS J1644+2619, suggesting a spatial association with the NLSy1. This is the sixth NLSy1 detected at high significance by Fermi-LAT so far. Notably, a significant increase of activity was observed in gamma-rays from FBQS J1644+2619 during 2012 July-October, and an increase of activity in V-band was detected by the Catalina Real-Time Sky Survey in the same period.

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F. D'Ammando, M. Orienti, J. Larsson, M. Giroletti. 2015-06-06. The first gamma-ray detection of the narrow-line Seyfert 1 FBQS J1644+2619. https://doi.org/10.1093/mnras%2Fstv1278

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