Thursday

High redshfit protoclusters are predicted to evolve into the most massive clusters in the local Universe containing the most massive elliptical galaxies. Galaxies are thought to form earlier and evolve more rapidly in these dense regions than in the field. However, it is not clear at what stage physical difference between galaxies in these different environments become observable. Studies at z3 show no such trend. Results of studies at 2.5nces in properties such as mass are just starting to emerge.

The SSA22 protocluster at z=3.1 is one of the most widely studied examples of a high redshift protocluster. It has been found to contain overdensities of star forming and massive red galaxies as well as 35 Lyman-alpha blobs. In previous work (Hine et al. 2016a) we have demonstrated that the Lyman break galaxies (LBGs) within the protocluster have a higher merger fraction than those in the field, indicating that the dense protocluster environment may be accelerating galaxy evolution. If this is the case then we might expect to find a difference in the physical properties of protocluster LBGs. I now present the results of a study using mutliwavelength photometry and SED fitting to compare the masses of the protocluster and field LBGs.