The merger-driven evolution of massive early-type galaxies

TL;DR

This paper investigates how mergers influence the structural, kinematic, and stellar population evolution of massive early-type galaxies, highlighting the roles of in-situ and ex-situ stars in their assembly history.

Contribution

It provides new insights into the evolution of the stellar mass-velocity dispersion relation and the impact of selection criteria on ETG studies.

Findings

Selection criteria significantly affect the observed properties of ETGs.

In-situ and ex-situ stellar populations have distinct roles in metallicity distributions.

Mergers drive the evolution of ETGs' structural and kinematic features.

Abstract

The evolution of the structural and kinematic properties of early-type galaxies (ETGs), their scaling relations, as well as their stellar metallicity and age contain precious information on the assembly history of these systems. We present results on the evolution of the stellar mass-velocity dispersion relation of ETGs, focusing in particular on the effects of some selection criteria used to define ETGs. We also try to shed light on the role that in-situ and ex-situ stellar populations have in massive ETGs, providing a possible explanation of the observed metallicity distributions.