Near-ultraviolet sources in the Great Observatories Origins Deep Survey fields.
DE MELLO D.F., DAHLEN T., GARDNER J.P. and GROGIN N.A.
Abstract (from CDS):
We present an ultraviolet-selected sample of 268 objects in the two fields of the Great Observatories Origins Deep Survey (GOODS). We used the parallel observations taken with the Wide Field Planetary Camera 2 in the U band (F300W), which covered 88% of the GOODS fields, to identify sources and selected only objects with GOODS Advanced Camera for Surveys 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 have redshifts 0.2<z<0.8. We used the spectral types obtained by photometric redshift fitting to identify starburst galaxies. We have also visually checked all objects and looked for tidal effects and nearby companions. We find that (1) 45% of the UV-selected galaxies are starbursts, (2) nearly 75% of the starbursts have tidal tails or show some peculiarity typical of interactions or mergers, and (3) ∼50% have companions within an area of 5''x5''. The UV-selected sample has an average rest-frame MB=-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 resemble either tadpoles, chains, or double-clump galaxies. Starbursts with tadpole or clump morphologies at z=0.8-1.3 have sizes comparable to Lyman break galaxies and compact UV-luminous galaxies.