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arXiv · 2209.01428

The structure at the centre of the giant radio galaxy GRS J0844+4627: a compact symmetric object?

A. Marecki·B. Sebastian·C. H. Ishwara-Chandra
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Abstract

We observed the core region of the giant radio galaxy GRS J0844+4627 with e-MERLIN at 1.52 and 5.07 GHz. These observations revealed that the apparent single feature at the centre of GRS J0844+4627, as seen by GMRT, consists of two components separated by 2.7 kpc in projection. Follow-up observations at 1.66 GHz using the EVN unveiled the complex morphologies of the two components. In particular, the south-western component identified with the SDSS J084408.85+462744.2 galaxy morphologically resembles a compact symmetric object (CSO) with a projected linear size of 115 pc. If the CSO hypothesis turns out to be correct, then the overall radio structure of GRS J0844+4627 is triple-double. Given that CSOs are considered young objects, GRS J0844+4627 would appear as a recently restarted active galaxy.

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A. Marecki, B. Sebastian, C. H. Ishwara-Chandra. 2022-09-03. The structure at the centre of the giant radio galaxy GRS J0844+4627: a compact symmetric object?. https://doi.org/10.1093/mnrasl%2Fslac105

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