Pérez-Millán, David
Mexico IRyA – UNAM
Star formation histories of cluster galaxies at high- and low-redshift
The observed properties of galaxies are strongly dependent on both their total stellar mass and their morphology. Furthermore, the environment is known to play a strong role in shaping them. The galaxy population in the local universe that is located in virialized clusters is found to be red, poorly star-forming, and mostly composed of early morphological types. Towards a holistic understanding of the mechanisms that drive galaxy evolution, we exploit data from the WINGS/OmegaWINGS local (0.04 < z < 0.07) galaxy cluster survey and the spectrophotometric code
Sinopsis, to study the role of both the local and global environments affecting stellar properties of galaxies such as star formation rate and star formation histories. We attempt to disentangle their effects from the intrinsic characteristics of the galaxies, in shaping the star formation activity at fixed morphological type and stellar mass.
Using data from the EDisCS (0.4 < z < 1.0), we compare our main results at low-z with those at intermediate-high redshift. We confirm some known findings, such as the morphological evolution through cosmic time and the larger star formation rate on the main sequence at higher redshift.
We also determine that clusters may have been more efficient in quenching star formation in the past, and we propose that the general higher star formation activity in galaxies at these redshifts may explain the Butcher-Oemler effect.