2005/07/22 by Davis, M., Gerke, B. F., Coil, A. L. +6
#Astrophysics (astro-ph) #FOS: Physical sciences
paper · doi:10.48550/arxiv.astro-ph/0507555
Number counts of galaxy clusters offer a very promising probe of the Dark Energy (DE) equation-of-state parameter, w. The basic goal is to measure abundances of these objects as a function of redshift, compare this to a theoretical prediction, and infer the values of cosmological parameters. Various teams have proposed such a measurement, including the South Pole Telescope, the Dark Energy Survey and the Red-Sequence Cluster Survey. The specific study discussed here detects clusters and smaller galaxy groups in the three-dimensional distribution of galaxies inferred from a large spectroscopic redshift survey. This method allows the abundance, N, of groups and clusters to be measured as a function of velocity dispersion, as well as of redshift, permitting a more sensitive test of cosmology.