Spirals, Bridges, and Tails: A GALEX UV Atlas of Interacting Galaxies
  We have used the GALEX ultraviolet telescope to study stellar populations and
star formation morphology in a well-defined sample of 42 nearby
optically-selected pre-merger interacting galaxy pairs. Galaxy interactions
were likely far more common in the early Universe than in the present, thus our
study provides a nearby well-resolved comparison sample for high redshift
studies. We have combined the GALEX NUV and FUV images with broadband optical
maps from the Sloan Digitized Sky Survey to investigate the ages and
extinctions of the tidal features and the disks. The distributions of the
UV/optical colors of the tidal features and the main disks of the galaxies are
similar, however, the tidal features are bluer on average in NUV - g when
compared with their own parent disks, thus tails and bridges are often more
prominent relative to the disks in UV images compared to optical maps. This
effect is likely due to enhanced star formation in the tidal features compared
to the disks rather than reduced extinction, however, lower metallicities may
also play a role. We have identified a few new candidate tidal dwarf galaxies
in this sample. Other interesting morphologies such as accretion tails and
`beads on a string' are also seen in these images. We also identify a possible
`Taffy' galaxy in our sample, which may have been produced by a head-on
collision between two galaxies. In only a few cases are strong tidal features
seen in HI maps but not in GALEX.
