Unveiling the most luminous Lyman-{\alpha} emitters in the epoch of reionisation

TL;DR

This paper reviews recent spectroscopic studies of luminous Lyman-alpha emitters from about 500 million years after the Big Bang, revealing their complex structures and early ionized environments during reionisation.

Contribution

It provides a comprehensive overview of recent observational results on high-redshift luminous galaxies, highlighting their properties and the insights gained into the epoch of reionisation.

Findings

Luminous Lyman-alpha emitters are complex, multi-component systems.

These galaxies likely reside in early ionised bubbles.

Metal traces are already present in these early galaxies.

Abstract

Distant luminous Lyman-alpha emitters are excellent targets for detailed observations of galaxies in the epoch of reionisation. Spatially resolved observations of these galaxies allow us to simultaneously probe the emission from young stars, partially ionised gas in the interstellar medium and to constrain the properties of the surrounding hydrogen in the circumgalactic medium. We review recent results from (spectroscopic) follow-up studies of the rest-frame UV, Lyman-alpha and [CII] emission in luminous galaxies observed ~500 Myr after the Big Bang with ALMA, HST/WFC3 and VLT/X-SHOOTER. These galaxies likely reside in early ionised bubbles and are complex systems, consisting of multiple well separated and resolved components where traces of metals are already present.