# Quenching and ram pressure stripping of simulated Milky Way satellite galaxies

## TL;DR

This study uses cosmological simulations to analyze how ram pressure stripping causes star formation quenching in Milky Way satellite galaxies, revealing mass and distance dependencies and distinguishing between infalling and backsplash populations.

## Contribution

It provides detailed predictions on satellite galaxy quenching mechanisms, especially highlighting ram pressure stripping's role and the distinction between different satellite populations.

## Key findings

- Ram pressure stripping is the main quenching mechanism.
- 50% of quenched satellites stop star formation within 1 Gyr of infall.
- Quenching depends on stellar mass and distance from host galaxy.

## Abstract

We present predictions for the quenching of star formation in satellite galaxies of the Local Group from a suite of 30 cosmological zoom simulations of Milky Way-like host galaxies. The Auriga simulations resolve satellites down to the luminosity of the classical dwarf spheroidal galaxies of the Milky Way. We find strong mass-dependent and distance-dependent quenching signals, where dwarf systems beyond 600 kpc are only strongly quenched below a stellar mass of $10^7$ M$_\odot$. Ram pressure stripping appears to be the dominant quenching mechanism and 50% of quenched systems cease star formation within 1 Gyr of first infall. We demonstrate that systems within a host galaxy's $R_{200}$ radius are comprised of two populations: (i) a first infall population that has entered the host halo within the past few Gyrs and (ii) a population of returning `backsplash' systems that have had a much more extended interaction with the host. Backsplash galaxies that do not return to the host galaxy by redshift zero exhibit quenching properties similar to galaxies within $R_{200}$ and are distinct from other external systems. The simulated quenching trend with stellar mass has some tension with observations, but our simulations are able reproduce the range of quenching times measured from resolved stellar populations of Local Group dwarf galaxies.