Mass loss and dynamical friction on the Fornax dSph galaxy in the Milky Way potential

TL;DR

This paper investigates how mass loss and dynamical friction influence the orbital decay of the Fornax dwarf galaxy in the Milky Way, showing that mass loss can mitigate dynamical friction effects and validating simplified models.

Contribution

It introduces a combined approach using a simplified single particle model with mass-loss extrapolated from N-body simulations to study dwarf galaxy dynamics.

Findings

Mass loss partially offsets dynamical friction effects.

Orbital decay is less pronounced when mass loss is considered.

Simplified models without dynamical friction can still effectively represent dwarf galaxy dynamics.

Abstract

We study the interplay between mass-loss and dynamical friction (DF) on the orbital decay of the Fornax dwarf spheroidal galaxy in the potential of the Milky Way (MW). Using a simplified single particle approach combined with a mass-loss rate extrapolated by $N-$body simulations we find that the the effect of a time-dependent mass partially compensates DF, and typically produces a much less evident decay of the pergalactic distance, thus confirming that $N-$body simulations in smooth MW potentials without DF can be taken as a good model of the dynamics of dwarf satellite galaxies.