Comparing Various Approaches to Simulating the Formation of Shell Galaxies

TL;DR

This paper compares test-particle and self-consistent simulations of shell galaxy formation, highlighting their agreement and discussing the importance of including effects like dynamical friction for accuracy.

Contribution

It introduces a comparison between different simulation approaches for shell galaxy formation and explores methods to incorporate missing physical effects.

Findings

Test-particle and self-consistent simulations agree on initial shell positions.

Dynamical friction and dwarf galaxy decay are crucial effects missing in simple models.

Inclusion of these effects improves simulation accuracy.

Abstract

The model of a radial minor merger proposed by Quinn (1984), which successfully reproduces the observed regular shell systems in shell galaxies, is ideal for a test-particle simulation. We compare such a simulation with a self-consistent one. They agree very well in positions of the first generation of shells but potentially important effects -- dynamical friction and gradual decay of the dwarf galaxy -- are not present in the test-particle model, therefore we look for a proper way to include them.