The environment and characteristics of low redshift galaxies detected by the Herschel-ATLAS

TL;DR

This study examines the properties and environments of low redshift galaxies detected by Herschel-ATLAS, revealing that detection is mainly limited to blue, star-forming galaxies, with galaxy color being a key factor over local density.

Contribution

It provides new insights into the types of galaxies detected by Herschel-ATLAS and highlights the importance of galaxy color over environment in detection likelihood.

Findings

H-ATLAS mainly detects blue, star-forming galaxies at low redshift.

Galaxy color influences H-ATLAS detectability more than local density.

Average dust temperature of detected galaxies is 25K ± 4K.

Abstract

We investigate the ultraviolet and optical properties and environment of low redshift galaxies detected in the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS) science demonstration data. We use the Sloan Digital Sky Survey seventh release and the Galaxy And Mass Assembly database to select galaxies with r_Petro < 19.0 mag in the redshift range 0.02 < z < 0.2 and look for their submillimeter counterparts in H-ATLAS. Our results show that at low redshift, H-ATLAS detects mainly blue/star-forming galaxies with a minor contribution from red systems which are highly obscured by dust. In addition we find that the colour of a galaxy rather than the local density of its environment determines whether it is detectable by H-ATLAS. The average dust temperature of galaxies that are simultaneously detected by both PACS and SPIRE is 25K \pm 4K, independent of environment. This analysis provides a glimpse of the potential of the H-ATLAS data to investigate the submillimeter properties of galaxies in the local universe.