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We investigate the properties of bright (MV <= -18) barred and unbarred disks in the Abell 901/902 cluster system at z~0.165 with the STAGES HST ACS survey. To identify and characterize bars, we use ellipse-fitting. We use visual classification, a Sersic cut, and a color cut to select disk galaxies, and find that the latter two methods miss 31% and 51%, respectively of disk galaxies identified through visual classification. This underscores the importance of carefully selecting the disk sample in cluster environments. However, we find that the global optical bar fraction in the clusters is ~30% regardless of the method of disk selection. We study the relationship of the optical bar fraction to host galaxy properties, and find that the optical bar fraction depends strongly on the luminosity of the galaxy and whether it hosts a prominent bulge or is bulgeless. Within a given absolute magnitude bin, the optical bar fraction increases for galaxies with no significant bulge component. Within each morphological type bin, the optical bar fraction increases for brighter galaxies. We find no strong trend (variations larger than a factor of 1.3) for the optical bar fraction with local density within the cluster between the core and virial radius (R ~ 0.25 to 1.2 Mpc). We discuss the implications of our results for the evolution of bars and disks in dense environments.
Massive compact galaxies seem to be more common at high redshift than in the local universe, especially in denser environments. To investigate the fate of such massive galaxies identified at z~2 we analyse the evolution of their properties in three c
The disk masses of four low surface brightness galaxies (LSB) were estimated using marginal gravitational stability criterion and the stellar velocity dispersion data which were taken from Pizzella et al., 2008 [1]. The constructed mass models appear
The formation of bars in disk galaxies is a tracer of the dynamical maturity of the population. Previous studies have found that the incidence of bars in disks decreases from the local Universe to z ~ 1, and by z > 1 simulations predict that bar feat
About one third of early-type barred galaxies host small-scale secondary bars. The formation and evolution of such double-barred galaxies remain far from being well understood. In order to understand the formation of such systems, we explore a large
We study the preferred environments of $z sim 0$ massive relic galaxies ($M_star gtrsim 10^{10}~mathrm{M_odot}$ galaxies with little or no growth from star formation or mergers since $z sim 2$). Significantly, we carry out our analysis on both a larg