Old stellar counter-rotating components in elliptical-spiral mergers: exploring the GalMer database

TL;DR

This study uses numerical simulations to explore how elliptical-spiral galaxy mergers can produce counter-rotating stellar components, revealing the kinematic outcomes and angular momentum transfer during such events.

Contribution

It provides new insights into the formation of counter-rotating components in merger remnants through detailed simulation analysis.

Findings

Counterrotation appears in both coplanar and non-coplanar mergers.

Disk components often preserve their initial spin, contributing to counterrotation.

External regions gain orbital angular momentum due to tidal forces.

Abstract

We investigate, by means of numerical simulations, the kinematics of elliptical-spiral merger remnants. Counterrotation can appear both in coplanar and in non-coplanar retrograde mergers, and it is mostly associated to the presence of a disk component, which preserves part of its initial spin. In turn, the external regions of the two interacting galaxies acquire part of the orbital angular momentum, due to the action of tidal forces.