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Restarting activity in the giant radio galaxy J1835+620

L. Lara·I. Marquez·W. D. Cotton·L. Feretti·G. Giovannini·J. M. Marcaide·T. Venturi
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Abstract

We present radio and optical observations of the peculiar radio galaxy J1835+620, a member of a new sample of large angular size radio galaxies selected from the NRAO VLA Sky Survey. Its optical counterpart is in a group of at least three galaxies and shows strong, narrow emission lines which allow us to measure its redshift as z=0.518. The derived cosmological distance places J1835+620 among the giant radio galaxies. The outstanding aspect of J1835+620 at radio wavelengths is the existence of two symmetric bright components within a typical Fanaroff-Riley type II structure. We interpret the source as the result of two distinct phases of core activity. Radio maps and radio polarization properties are consistent with a dense new ejection evolving through an older underlying jet. We suggest that interaction with nearby galaxies could be the reason for restarting the activity in J1835+620.

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L. Lara, I. Marquez, W. D. Cotton, L. Feretti, G. Giovannini, J. M. Marcaide, T. Venturi. 1999-06-17. Restarting activity in the giant radio galaxy J1835+620. https://arxiv.org/abs/astro-ph/9906287

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