Far UV and X-ray observation: a hot view of shell galaxies

TL;DR

This study investigates shell galaxies using Far UV and X-ray observations to understand their recent accretion events, stellar rejuvenation, and evolution driven by merging processes.

Contribution

It provides preliminary UV and X-ray data analysis of three shell galaxies to explore their evolutionary history and stellar population rejuvenation.

Findings

UV morphology reveals signs of recent star formation.

X-ray data suggest ongoing or past merging activity.

Results support the role of accretion in galaxy evolution.

Abstract

Shell galaxies are considered the debris of recent accretion/merging episodes. Their high frequency in low density environments suggest that such episodes could drive the secular evolution for at least some fraction of the early-type galaxy population. We present here the preliminary results of ultraviolet and X-ray data for a sample of three shell galaxies, namely NGC 474, NGC 7070A and ESO 2400100. The Far UV morphology and photometry are derived using the observations obtained with the Galaxy Evolution Explorer and the XMM- Newton Optical Monitor. We aim at investigating the rejuvenation processes in the stellar population using the UV information as well as at gaining information about the possible evolution with time of the X-ray emission due interaction/merging processes.