# WALLABY Early Science - II. The NGC 7232 galaxy group

## TL;DR

This paper presents early science results from ASKAP's WALLABY survey, detecting 17 HI sources in the NGC 7232 galaxy group, including new galaxy detections and tidal debris, demonstrating ASKAP's capability for wide-field HI mapping.

## Contribution

First HI observations of the NGC 7232 group with ASKAP, revealing new galaxy sources and tidal features, showcasing the survey's potential for studying galaxy interactions.

## Key findings

- Detected 17 HI sources, including 11 galaxies with stellar counterparts.
- Identified 6 HI clouds as tidal debris associated with galaxy interactions.
- Discovered a potential progenitor of a tidal dwarf galaxy with M_HI ~ 3 x 10^8 M_sun.

## Abstract

We report on neutral hydrogen (HI) observations of the NGC 7232 group with the Australian Square Kilometre Array Pathfinder (ASKAP). These observations were conducted as part of the Wide-field ASKAP L-Band Legacy All-sky Blind surveY (WALLABY) Early Science program with an array of 12 ASKAP antennas equipped with Phased Array Feeds, which were used to form 36 beams to map a field of view of 30 square degrees. Analyzing a subregion of the central beams, we detect 17 HI sources. Eleven of these detections are identified as galaxies and have stellar counterparts, of which five are newly resolved HI galaxy sources. The other six detections appear to be tidal debris in the form of HI clouds that are associated with the central triplet, NGC 7232/3, comprising the spiral galaxies NGC 7232, NGC7232B and NGC7233. One of these HI clouds has a mass of M_HI ~ 3 x 10^8 M_sol and could be the progenitor of a long-lived tidal dwarf galaxy. The remaining HI clouds are likely transient tidal knots that are possibly part of a diffuse tidal bridge between NGC 7232/3 and another group member, the lenticular galaxy IC 5181.