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arXiv · 2406.14889

J0011+3217: A peculiar radio galaxy with a one-sided secondary lobe and misaligned giant primary lobes

Shobha Kumari·Sabyasachi Pal·Martin J. Hardcastle·Maya A. Horton
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Abstract

From the LOFAR Two-metre Sky Survey second data release (LoTSS DR2) at 144 MHz, we identified a peculiar radio galaxy, J0011+3217. It has a large, one-sided diffuse secondary wing that stretches up to 0.85 Mpc (roughly 85\% of the size of the primary lobe). The linear size of the primary lobe of the galaxy is 0.99 Mpc. This peculiar source is a giant radio galaxy with a misaligned primary lobe. There is an optical galaxy 16 kpc (7 arcsec) from the host active galactic nucleus of J0011+3217. J0011+3217 has a radio luminosity of $1.65\times 10^{26}$ W Hz$^{-1}$ at 144 MHz with a spectral index of $-0.80$ between 144 and 607 MHz. J0011+3217 is located 1.2 Mpc from the centre of the Abell 7 cluster. The Abell 7 cluster has a redshift of 0.104 and a mass ($M_{500}$) of 3.71 $\times 10^{14}$ M$_\odot$. The cluster is associated with strong X-ray emission. We studied the X-ray emission around the cluster and from the region surrounding J0011+3217 using an XMM-Newton image of J0011+3217, and we analysed the velocity structure and spatial distribution of galaxies in the cluster, showing that J0011+3217 inhabits an offset group of galaxies that are moving with respect to Abell 7. The off-axis distortion, or bending, of the primary lobe of J0011+3217 in the outer edges has a strong effect on the relative motion of the surrounding medium; this in turn causes the bending of the jets in the opposite direction of the cluster (like wide-angle tailed sources). We suggest that the morphology of J0011+3217 is influenced by ram pressure created by the Abell 7 cluster, highlighting the complex interactions between the source and the surrounding cluster environment.

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Shobha Kumari, Sabyasachi Pal, Martin J. Hardcastle, Maya A. Horton. 2024-06-21. J0011+3217: A peculiar radio galaxy with a one-sided secondary lobe and misaligned giant primary lobes. https://doi.org/10.1051/0004-6361/202347367

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