Dorado and its member galaxies II. A UVIT picture of the NGC 1533 substructure

TL;DR

This study uses UVIT imaging to analyze star formation and interaction features in the NGC 1533 substructure within the Dorado galaxy group, revealing FUV emission patterns and potential interaction signatures.

Contribution

It provides new FUV imaging data of the NGC 1533 substructure, enhancing understanding of star formation and galaxy interactions in this nearby galaxy group.

Findings

Detection of FUV emission consistent with disk structures in all three galaxies.

FUV emission extends to optical sizes in IC 2038 and shows compact features in NGC 1533.

Identification of faint FUV emission linked to HI structures around NGC 1533.

Abstract

Dorado is a nearby (17.69 Mpc) strongly evolving galaxy group in the Southern Hemisphere. We are investigating the star formation in this group. This paper provides a FUV imaging of NGC 1533, IC 2038 and IC 2039, which form a substructure, south west of the Dorado group barycentre. FUV CaF2-1 UVIT-Astrosat images enrich our knowledge of the system provided by GALEX. In conjunction with deep optical wide-field, narrow-band Halpha and 21-cm radio images we search for signatures of the interaction mechanisms looking in the FUV morphologies and derive the star formation rate. The shape of the FUV luminosity profile suggests the presence of a disk in all three galaxies. FUV emission is detected out to the optical size for IC 2038, and in compact structures corresponding to Halpha and HII bright features in NGC 1533. A faint FUV emission, without an optical counterpart, reminiscent of the HI structure that surrounds the outskirts of NGC 1533 and extends up to IC 2038/2039, is revealed above the local background noise.