On the encounter between the GASP galaxy JO36 and the radio plume of GIN 049

TL;DR

This paper reports the discovery of an unprecedented interaction between a radio galaxy's plume and a spiral galaxy, revealing how such encounters can trigger star formation and reshape radio plasma.

Contribution

It presents the first observation of a spiral galaxy interacting with a radio plume, showing effects on star formation and radio plasma structure.

Findings

Interaction occurred 200-500 Myr ago

Triggered a star formation rate burst of ~14 M_sun/yr

Reshaped radio plasma via magnetic draping

Abstract

We report on the serendipitous discovery of an unprecedented interaction between the radio lobe of a radio galaxy and a spiral galaxy. The discovery was made thanks to LOFAR observations at 144 MHz of the galaxy cluster Abell 160 ($z=0.04317$) provided by the LOFAR Two-metre Sky Survey. The new low-frequency observations revealed that one of the radio plumes of the central galaxy GIN 049 overlaps with the spiral galaxy JO36. Previous studies carried out with MUSE revealed that the warm ionized gas in the disk of JO36, traced by the H$\alpha$ emission, is severely truncated with respect to the stellar disk. We further explore this unique system by including new uGMRT observations at 675 MHz to map the spectral index. The emerging scenario is that JO36 has interacted with the radio plume in the past 200-500 Myr. The encounter resulted in a positive feedback event for JO36 in the form of a star formation rate burst of $\sim14$ $M_\odot$ yr$^{-1}$. In turn, the galaxy passage left a trace in the radio-old plasma by re-shaping the old relativistic plasma via magnetic draping.