We present a catalog of 20,977 extended low-surface-brightness galaxies (LSBGs) identified in ∼ 5000 deg2 from the first three years of imaging data from the Dark Energy Survey (DES). Based on a single-component Sérsic model fit, we define extended LSBGs as galaxies with g-band effective radii Reff (g) > 2.500 and mean surface brightness µ¯eff (g) > 24.3 mag arcsec−2. We find that the distribution of LSBGs is strongly bimodal in (g − r) vs. (g − i) color space. We divide our sample into red (g − i ≥ 0.59) and blue (g − i < 0.59) galaxies and study the properties of the two populations. Redder LSBGs are more clustered than their blue counterparts, and are correlated with the distribution of nearby (z < 0.10) bright galaxies. Red LSBGs constitute ∼ 35% of our LSBG sample, and ∼ 30% of these are located within 1 deg of low-redshift galaxy groups and clusters (compared to ∼ 8% of the blue LSBGs). For nine of the most prominent galaxy groups and clusters, we calculate the physical properties of associated LSBGs assuming a redshift derived from the host system. In these systems, we identify 108 objects that can be classified as ultra-diffuse galaxies, defined as LSBGs with projected physical effective radii Reff > 1.5 kpc. The wide-area sample of LSBGs in DES can be used to test the role of environment on models of LSBG formation and evolution.
|Original language||English (US)|
|State||Published - Jun 7 2020|
- Catalogs — surveys
- Low surface brightness galaxies
ASJC Scopus subject areas