AAS 198th Meeting, June 2001
Session 54. Galaxy Evolution and Surveys
Display, Wednesday, June 6, 2001, 10:00am-7:00pm, Exhibit Hall

## [54.08] Surface Brightness and Color Profiles of Galaxies in the Hubble Deep Field

P. Moth, R.J. Elston (University of Florida)

We fit elliptical isophotes to the Hubble Deep Field North WFPC-2 and NICMOS data to study the rest-frame near ultra-violet and optical color and surface brightness profiles of 33 intermediate redshift galaxies ( 0.5 \leq z \leq 1.2) and 50 high redshift galaxies (2.0 \leq z \leq 3). From the fits to the surface brightness profiles we find that although galaxies with exponential profiles dominate at all epochs, there seems to be a decrease in the spheroidal population with look-back time. Along with the evolution in the surface brightness profiles, we find also an evolution in the color profiles. At intermediate redshifts, the galaxies possess negative color gradients indicating a reddening towards the center of the profile similar to local samples, whereas at high redshifts, the galaxies possess positive color gradients indicating that star formation is more centrally concentrated in disks. Mergers and interactions may be responsible for the evolution seen in the surface brightness and color profiles of the galaxies in the Hubble Deep Field North.

P.M. would like to acknowledge the Florida Space Grant Consortium for their support.