Mass accretion rates of clusters of galaxies: CIRS and HeCS

We use a new spherical accretion recipe tested on N -body simulations to measure the observed mass rate (MAR) of 129 clusters in Cluster Infall Regions Sloan Digital Sky Survey (CIRS) and Hectospec (HeCS). The cover redshift range 0.01 < z 0.30 ?10 14 ? 10 15 h ?1 M ? . Based three-dimensional profiles simulated reaching beyond virial radius, our returns MARs that agree with based merger trees. adopt this estimate MAR real measurements profile out ?3 R 200 caustic method these large radii. demonstrate validity estimates by applying same approach set mock surveys sample 2000 median = as well 50 : are unbiased within 19% clusters. CIRS HeCS increases accreting cluster, which is excellent agreement growth ?CDM model.