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arXiv · 2210.06100

RAD@home citizen science discovery of an AGN spewing a large unipolar radio bubble onto its merging companion galaxy

Ananda Hota·Pratik Dabhade·Sravani Vaddi·Chiranjib Konar·Sabyasachi Pal·Mamta Gulati·C S. Stalin·Ck Avinash·Avinash Kumar·Megha Rajoria·Arundhati Purohit
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Abstract

AGN feedback during galaxy merger has been the most favoured model to explain black hole-galaxy co-evolution. However, how the AGN-driven jet/wind/radiation is coupled with the gas of the merging galaxies, which leads to positive feedback, momentarily enhanced star formation, and subsequently negative feedback, a decline in star formation, is poorly understood. Only a few cases are known where the jet and companion galaxy interaction leads to minor off-axis distortions in the jets and enhanced star formation in the gas-rich minor companions. Here, we briefly report one extraordinary case, RAD12, discovered by RAD@home citizen science collaboratory, where for the first time a radio jet-driven bubble ~137 kpc is showing a symmetric reflection after hitting the incoming galaxy which is not a gas-rich minor but a gas-poor early-type galaxy in a major merger. Surprisingly, neither positive feedback nor any radio lobe on the counter jet side, if any, is detected. It is puzzling if RAD12 is a genuine one-sided jet or a case of radio lobe trapped, compressed and re-accelerated by shocks during the merger. This is the first imaging study of RAD12 presenting follow-up with the GMRT, archival MeerKAT radio data and CFHT optical data.

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Ananda Hota, Pratik Dabhade, Sravani Vaddi, Chiranjib Konar, Sabyasachi Pal, Mamta Gulati, C S. Stalin, Ck Avinash, Avinash Kumar, Megha Rajoria, Arundhati Purohit. 2022-10-12. RAD@home citizen science discovery of an AGN spewing a large unipolar radio bubble onto its merging companion galaxy. https://doi.org/10.1093/mnrasl%2Fslac116

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