Interacting LAEs at z = 5.1. Episodic star formation in a group of LAEs at z= 5.07

TL;DR

This study confirms a pair of high-redshift Lyman Alpha emitters at z=5.07, demonstrating episodic star formation and interaction, providing insights into early galaxy formation and evolution.

Contribution

First spectroscopic confirmation of interacting LAEs at z=5.07 showing episodic star formation and galaxy interactions in the early universe.

Findings

Confirmed two LAEs at z=5.07 with spectroscopic data.

Evidence of recent and past starburst activity in the galaxies.

Indications of galaxy interaction and merging processes.

Abstract

We are undertaking a search for high-redshift low luminosity Lyman Alpha sources in the SHARDS survey. Among the pre-selected Lyman Alpha sources 2 candidates were spotted, located 3.19 arcsec apart, and tentatively at the same redshift. Here we report on the spectroscopic confirmation with GTC of the Lyman Alpha emission from this pair of galaxies at a confirmed spectroscopic redshifts of z=5.07. Furthermore, one of the sources is interacting/merging with another close companion that looks distorted. Based on the analysis of the spectroscopy and additional photometric data, we infer that most of the stellar mass of these objects was assembled in a burst of star formation 100 Myr ago. A more recent burst (2 Myr old) is necessary to account for the measured Lyman Alpha flux. We claim that these two galaxies are good examples of Lyman Alpha sources undergoing episodic star formation. Besides, these sources very likely constitute a group of interacting Lyman Alpha emitters (LAEs).