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arXiv · 1704.03881

Kiloparsec-scale emission in the narrow-line Seyfert 1 galaxy Mrk 783

E. Congiu·M. Berton·M. Giroletti·R. Antonucci·A. Caccianiga·P. Kharb·M. L. Lister·L. Foschini·S. Ciroi·V. Cracco·M. Frezzato·E. Järvelä·G. La Mura·J. L. Richards·P. Rafanelli
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Abstract

We present the first results of a radio survey of 79 narrow-line Seyfert 1 (NLS1) carried out with the Karl G. Jansky Very Large Array (JVLA) at 5 GHz in A configuration aimed at studying the radio properties of these sources. We report the detection of extended emission in one object: Mrk 783. This is intriguing, since the radio-loudness parameter R of this object is close to the threshold between radio-quiet and radio-loud active galactic nuclei (AGN). The galaxy is one of the few NLS1 showing such an extended emission at z < 0.1. The radio emission is divided in a compact core component and an extended component, observed on both sides of the nucleus and extending from 14 kpc south-east to 12 kpc north-west. There is no sign of a collimated jet, and the shape of the extended component is similar to those of some Seyfert galaxies. The properties of the emission are compatible with a relic produced by the intermittent activity cycle of the AGN.

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E. Congiu, M. Berton, M. Giroletti, R. Antonucci, A. Caccianiga, P. Kharb, M. L. Lister, L. Foschini, S. Ciroi, V. Cracco, M. Frezzato, E. Järvelä, G. La Mura, J. L. Richards, P. Rafanelli. 2017-05-04. Kiloparsec-scale emission in the narrow-line Seyfert 1 galaxy Mrk 783. https://doi.org/10.1051/0004-6361%2F201730616

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