MaxBCG Galaxy Clusters: Laboratories for Galaxy Evolution and Tools for Cosmology

Regents Of The University Of Michigan - Ann Arbor, Ann Arbor MI

Investigators

Abstract

Dr McKay and his group will study a set of rich clusters of galaxies, the 'MaxBCG catalog', which they have identified from the galaxy database of the Sloan Digital Sky Survey (SDSS). They will reprocess the images from the SDSS to obtain better measures of the galaxy brightness. They will use the Magellan telescopes to measure galaxy motions within the cluster, to estimate the mass of each cluster. Measuring weak gravitational lensing -- the way in which the cluster's gravitational pull distorts the path of light from distant galaxies lying behind it -- will provide additional mass estimates. The results of this study will relate measures of the optical richness (the number and brightness of its member galaxies) of each cluster to its mass. The results of this work will be used to test theories of cosmic structure formation, which can predict how the mass that galaxy clusters should build up through cosmic time. Galaxy clusters are widely used in probing dark energy and in cosmological tests of General Relativity, so this research will have a broad scientific impact. Dr. McKay and his group have an excellent record in mentoring undergraduate researchers, and will involve both undergraduate and graduate students in this work. He will also teach a research seminar for incoming undergraduates in which they will perform analysis projects based on public SDSS data.