Feedback in low-mass galaxies in the early Universe

TL;DR

This paper discusses how feedback from massive stars in early low-mass galaxies influenced star formation and contributed to the reionization of the universe by enabling ionizing radiation escape.

Contribution

It highlights the role of feedback in low-mass galaxies during the early universe and its impact on galaxy evolution and cosmic reionization.

Findings

Feedback causes galactic outflows in high star formation rate galaxies.

Feedback likely enabled ionizing radiation escape in early low-mass galaxies.

Feedback influenced the transition of hydrogen from neutral to ionized.

Abstract

The formation, evolution and death of massive stars release large quantities of energy and momentum into the gas surrounding the sites of star formation. This process, generically termed 'feedback', inhibits further star formation either by removing gas from the galaxy, or by heating it to temperatures that are too high to form new stars. Observations reveal feedback in the form of galactic-scale outflows of gas in galaxies with high rates of star formation, especially in the early Universe. Feedback in faint, low-mass galaxies probably facilitated the escape of ionizing radiation from galaxies when the Universe was about 500 million years old, so that the hydrogen between galaxies changed from neutral to ionized--the last major phase transition in the Universe.