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arXiv · 1701.09111

Radio and gamma-ray loud narrow-line Seyfert 1 galaxies in the spotlight

V. Karamanavis·E. Angelakis·S. Komossa·I. Myserlis·D. Blinov·J. A. Zensus
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Abstract

Narrow-line Seyfert 1 (NLS1) galaxies provide us with unique insights into the drivers of AGN activity under extreme conditions. Given their low black hole (BH) masses and near-Eddington accretion rates, they represent a class of galaxies with rapidly growing supermassive BHs in the local universe. Here, we present the results from our multi-frequency radio monitoring of a sample of γ-ray loud NLS1 galaxies (γNLS1s), including systems discovered only recently, and featuring both the nearest and the most distant γNLS1s known to date. We also present high-resolution radio imaging of 1H 0323+342, which is remarkable for its spiral or ring-like host. Finally, we present new radio data of the candidate γ-emitting NLS1 galaxy RX J2314.9+2243, characterized by a very steep radio spectrum, unlike other γNLS1s.

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V. Karamanavis, E. Angelakis, S. Komossa, I. Myserlis, D. Blinov, J. A. Zensus. 2017-01-31. Radio and gamma-ray loud narrow-line Seyfert 1 galaxies in the spotlight. https://doi.org/10.1017/s1743921317001065

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