Near-Ultraviolet Sources in the Great Observatories Origins Deep Survey Fields

Abstract

We present an Ultraviolet (UV) selected sample of 268 objects in the two fields of the Great Observatories Origins Deep Survey (GOODS). We used the parallel observations taken with WFPC2 in the U--band (F300W) which covered 88% of the GOODS fields to identify sources and selected only objects with GOODS/ACS counterparts. Spectroscopic redshifts for 95 of these sources are available and we have used the multiwavelength GOODS data to estimate photometric redshifts for the others. Most of the objects are between 0.2<z<0.8. We used the spectral types obtained by the photometric redshift fitting to identify the starburst galaxies. We have also visually checked all objects and looked for tidal effects and nearby companions. We find that (i) 45% of the UV-selected galaxies are starbursts, (ii) nearly 75% of the starbursts have tidal tails or show some peculiarity typical of interactions or mergers, (iii) ~50% have companions within an area of 5x5 arcsec. The UV-selected sample has an average rest-frame M_B=--19.9 +- 0.1. The bluest objects in the sample (U-B < 0.2 and B-V < 0.1) are at 1.1<z<1.9 and have peculiar morphologies that resembles either tadpoles, chains, or double-clump galaxies. Starbursts with tadpole or clump morphology at z=0.8-1.3 have sizes comparable to LBGs and compact Ultraviolet-luminous galaxies (UVLGs).