A Parameterized Galaxy Catalog Simulator for Testing Cluster Finding, Mass Estimation, and Photometric Redshift Estimation in Optical and Near-infrared Surveys

Abstract

We present a galaxy catalog simulator that converts N -body simulations with halo and subhalo catalogs into mock, multiband photometric catalogs. The simulator assigns galaxy properties to each subhalo in a way that reproduces the observed cluster galaxy halo occupation distribution, the radial and mass-dependent variation in fractions of blue galaxies, the luminosity functions in the cluster and the field, and the color-magnitude relation in clusters. Moreover, the evolution of these parameters is tuned to match existing observational constraints. Parameterizing an ensemble of cluster galaxy properties enables us to create mock catalogs with variations in those properties, which in turn allows us to quantify the sensitivity of cluster finding to current observational uncertainties in these properties. Field galaxies are sampled from existing multiband photometric surveys of similar depth. We present an application of the catalog simulator to characterize the selection function and contamination of a galaxy cluster finder that utilizes the cluster red sequence together with galaxy clustering on the sky. We estimate systematic uncertainties in the selection to be at the ≤15% level with current observational constraints on cluster galaxy populations and their evolution. We find the contamination in this cluster finder to be ~35% to redshift z ~ 0.6. In addition, we use the mock galaxy catalogs to test the optical mass indicator B gc and a red-sequence redshift estimator. We measure the intrinsic scatter of the B gc -mass relation to be approximately log normal with ##IMG## [http://ej.iop.org/images/0004-637X/747/1/58/apj417488ieqn1.gif] {$\sigma _{\log _{10M\sim 0.25$ and we demonstrate photometric redshift accuracies for massive clusters at the ~3% level out to z ~ 0.7.