The evolving galaxy population of cluster Cl0024+1654

While many physical mechanisms have been proposed as the cause of luminosity, color, and morphological evolution in cluster galaxies, observational signatures of these mechanisms remain largely untested. This dissertation is an effort to pinpoint evolutionary signatures through an intense investigation of the spectral properties, structures, and kinematics of disk galaxies in z = 0.4 cluster Cl0024+1654.; Our study employs measurements from deep Keck spectroscopy of the cluster and extensive imaging available from the Hubble Space Telescope archive. In contrast to previous measurements of a centrally-concentrated distribution of galaxies in Cl0024, we find significant evidence for cluster substructure. This evidence includes three peaks in the cluster redshift distribution and an elongated spatial distribution. The unrelaxed nature of Cl0024 is likely affecting its consituent galaxy population. We find a high fraction of blue galaxies (∼20%) and a large proportion of disk-dominated, emission-line cluster members (∼50%) in Cl0024 as compared to local clusters.; We focus on the structures of Cl0024 S0s and blue galaxies for observational clues about their ongoing evolution. We find no evidence for rapid evolution of cluster S0s from analysis of their colors and color gradients. Furthermore, we find that sub-classification of Cl0024 early-types into S0s and ellipticals may be biased, dependent upon viewing angle. Blue cluster members appear distinct from blue field galaxies at the same redshift. Specifically, the cluster members are somewhat redder and have smoother light profiles than their field counterparts. This result supports the claim that high-density environments suppress star formation in spirals, perhaps via galaxy harassment.; Lastly, we investigate the two-dimensional kinematics of a sample of 15 cluster members through rotation curve analysis, yielding the largest Tully-Fisher study of disk galaxies in a z > 0.2 cluster. We find evidence for ∼0.7 mag luminosity brightening in Cl0024 as compared to local field and cluster samples. The most overluminous Cl0024 members tend to be the most small, blue, slowly rotating galaxies in our sample—likely progenitors of present-day cluster dwarfs. We find little evidence for galaxy interactions as an evolutionary driver from our Tully-Fisher analysis.