Evolution of star forming dwarf galaxies: Characterizing the star formation scenarios

TL;DR

This study employs a combined chemical evolution and stellar population synthesis model to identify star formation scenarios that best match observed properties of star-forming dwarf galaxies, favoring bursting over continuous modes.

Contribution

It demonstrates that a bursting star formation model with specific efficiencies and inter-burst times best reproduces observed galaxy spectra and colors.

Findings

Bursting star formation scenario fits observed data

Star formation efficiency around 20% of gas mass

Inter-burst times longer than 100 Myr, likely around 1 Gyr

Abstract

We use the self-consistent model technique developed by Mart\'in-Manj\'on et al. (2008) that combines the chemical evolution with stellar population synthesis and photo-ionization codes, to study the star formation scenarios capable of reproducing the observed properties of star-forming galaxies. The comparison of our model results with a database of HII galaxies shows that the observed spectra and colors of the present burst and the older underlying population are reproduced by models in a bursting scenario with star formation efficiency involving close to 20 per cent of the total mass of gas, and inter-burst times longer than 100 Myr, and more probably around 1 Gyr. Other modes like gasping and continuous star formation are not favored.