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arXiv · 1210.0546

To be or not to be a blazar. The case of the Narrow-Line Seyfert 1 SBS 0846+513

F. D'Ammando·M. Orienti·J. Finke
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Abstract

The presence of a relativistic jet in some radio-loud Narrow-Line Seyfert 1s (NLSy1) galaxies, first suggested by their variable radio emission and the flat radio spectra, is now confirmed by the Fermi-LAT detection of five NLSy1s in gamma rays. In particular, a strong gamma-ray flare from SBS 0846+513 was observed in 2011 June by Fermi-LAT reaching a gamma-ray luminosity (0.1-300 GeV) of about 10^48 erg/s, comparable to that of bright flat spectrum radio quasars. Apparent superluminal velocity in the jet was inferred from 2011-2012 VLBA images, suggesting the presence of a highly relativistic jet. Both the power released by this object during the flaring activity and the apparent superluminal velocity are strong indicators of the presence of a relativistic jet as powerful as those in blazars. In addition, variability and spectral properties in radio and gamma-ray bands indicate a blazar-like behaviour, suggesting that, except for some distinct optical characteristics, SBS 0846+513 could be considered as a young blazar at the low end of the blazar's black hole mass distribution.

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F. D'Ammando, M. Orienti, J. Finke. 2012-10-01. To be or not to be a blazar. The case of the Narrow-Line Seyfert 1 SBS 0846+513. https://doi.org/10.1063/1.4772324

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