HI content and star formation in the interacting galaxy Arp86

Abstract

We present the results of Giant Metrewave Radio Telescope (GMRT) observations of the interacting system Arp86 in both neutral atomic hydrogen, H i, and in radio continuum at 240 606 and 1394 MHz. In addition to H i emission from the two dominant galaxies, NGC 7752 and NGC 7753, these observations show a complex distribution of H i tails and bridges due to tidal interactions. The regions of highest column density appear related to the recent sites of intense star formation. H i column densities ∼1–1.5 × 1021 cm−2 have been detected in the tidal bridge which is bright in Spitzer image as well. We also detect H i emission from the galaxy 2MASX J23470758+2926531, which is shown to be a part of this system. We discuss the possibility that this could be a tidal dwarf galaxy. The radio continuum observations show evidence of a non-thermal bridge between NGC 7752 and NGC 7753, and a radio source in the nuclear region of NGC 7753 consistent with it having a low-ionization nuclear emission region nucleus.