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arXiv · 1805.06459

On the orientation of Narrow Line Seyfert I

Tullia Sbarrato·Massimo Dotti·Giancarlo Ghirlanda·Fabrizio Tavecchio
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Abstract

We study a sample of Narrow-line Seyfert 1 galaxies (NLS1) in their optical and radio features, in order to understand the differences between their radio silent, radio-loud and radio-quiet subclasses. We first show that the different redshift and mass distributions of radio-loud and -quiet NLS1s could be ascribed to observational biases. We then present a geometrical model according to which most of the different observational features of radio-loud and radio-quiet NLS1s are ascribed to the orientation of an intrinsically structured jet. We estimate the fraction of intrinsically jetted sources among NLS1s that justifies the observed radio-detected population. Noticeably, under the assumptions of the geometrical model, we derive a fraction of jetted sources significantly larger than in standard AGN.

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Tullia Sbarrato, Massimo Dotti, Giancarlo Ghirlanda, Fabrizio Tavecchio. 2018-05-16. On the orientation of Narrow Line Seyfert I. https://doi.org/10.1051/0004-6361%2F201732451

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