We present a catalog of 23790 extended low-surface-brightness galaxies (LSBGs) identified in ~5000{deg}^2^ from the first three years of imaging data from the Dark Energy Survey (DES). Based on a single-component Sersic model fit, we define extended LSBGs as galaxies with g-band effective radii R_eff_(g)>2.5" and mean surface brightness {mu}eff(g)>24.2mag/arcsec^2^}. We find that the distribution of LSBGs is strongly bimodal in (g-r) versus (g-i) color space. We divide our sample into red (g-i>=0.60) and blue (g-i<0.60) 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 (z1.5kpc and central surface brightness {mu}0(g)>24.0mag/arcsec^2^. The wide-area sample of LSBGs in DES can be used to test the role of environment on models of LSBG formation and evolution.
Cone search capability for table J/ApJS/252/18/table2 (Characteristics of the most prominent density peaks and their association)
Cone search capability for table J/ApJS/252/18/tabled1 (Extended low-surface-brightness galaxy catalog)