Breathing in Low Mass Galaxies: A Study of Episodic Star Formation

TL;DR

This paper uses simulations to study episodic star formation in low mass galaxies, revealing how supernova feedback causes cyclical gas flows and star formation bursts, with implications for galaxy evolution.

Contribution

It introduces a physically motivated simulation model showing how supernova feedback drives episodic star formation in dwarf galaxies.

Findings

Star formation occurs in bursts due to feedback-driven gas outflows.

Stellar velocity dispersions are at least half the halo velocity at the virial radius.

Simulated star formation histories resemble those of observed Local Group dwarfs.

Abstract

We simulate the collapse of isolated dwarf galaxies using SPH + N-Body simulations including a physically motivated description of the effects of supernova feedback. As the gas collapses and stars form, the supernova feedback disrupts enough gas to temporarily quench star formation. The gas flows outward into a hot halo, where it cools until star formation can continue once more and the cycle repeats. The star formation histories of isolated Local Group dwarf galaxies exhibit similar episodic bursts of star formation. We examine the mass dependence of the stellar velocity dispersions and find that they are no less than half the velocity of the halos measured at the virial radius.