Disruption of Dwarf Satellite Galaxies without Dark Matter

TL;DR

This study uses N-body simulations to explore how dwarf satellite galaxies can appear disrupted and exhibit high mass-to-light ratios without containing dark matter, challenging traditional assumptions.

Contribution

It demonstrates that some dwarf spheroidal galaxies' high M/L ratios may result from out-of-equilibrium states rather than dark matter presence.

Findings

Disrupted satellites can mimic dSph galaxies for over 1 Gyr.

High M/L ratios can occur without dark matter in out-of-equilibrium conditions.

Simulations suggest some observed dSphs may not be dark matter dominated.

Abstract

The evolution of a satellite galaxy of a Milky Way like galaxy has been studied using N-Body simulations. The initial satellites, containing one million particles, have been simulated by a Plummer sphere, while the potential of the host galaxy is a three component rigid potential: disc, bulge and dark matter halo. It has been found that several orbits of the satellites allow for the existence, for about 1 Gyr or more, of an out-of-equilibrium body that could be interpreted as a dSph satellite galaxy of the Milky Way. In addition, from the study of the evolution of the mass-to-light ratios of satellites that show a disrupted phase it has been found that it is possible that some dSph galaxies of the Milky Way with large M/L ratios might not be dark matter dominated and that their high mass to light ratios are observed because they are out of equilibrium objects.