  We have studied the morphologies of luminous infrared galaxies (LIRGs;
L_IR(8-1000um)>10^11 Lsun) at 0.3< z<1.4 in the HST Ultradeep Field (UDF) by
calculating concentration and asymmetry indices and comparing the results with
similar calculations for: (1) galaxies at similar redshift that are less
infrared-active; and (2) local LIRGs. We find that the high-redshift samples
are dominated by galaxies with concentrations similar to local late-type disk
galaxies; however, they are significantly more asymmetric than most local
galaxies but are similar in both regards to local LIRGs. On average, the
high-redshift infrared-active galaxies are slightly more asymmetric than the
less-active ones, although they do include a significantly higher portion of
highly asymmetric (merging?) systems and a lower portion of more concentrated,
symmetric ones. The morphological similarity of infrared-active and typical
infrared-inactive galaxies at high-redshift suggests that they may be from the
same parent population, but are in different stages of an episodic star
formation process. The similarity between high-redshift and local LIRGs
suggests that a certain level of asymmetry is generally associated with
LIRG-level activity.
