An Optical Catalog of Galaxy Clusters Obtained from an Adaptive Matched Filter Finder Applied to SDSS DR9 Data

Abstract

We present a new galaxy cluster catalog constructed from SDSS DR9 using an Adaptive Matched Filter technique. Our main catalog has 46,479 galaxy clusters with richness $Λ_{200} > 20$ in the redshift range 0.045 $\le z <$ 0.641 in $\sim$11,500 $deg^{2}$ of the sky. Angular position, richness, core and virial radii and redshift estimates for these clusters, as well as their error analysis are provided. We also provide an extended version with a lower richness cut, containing 79,368 clusters. This version, in addition to the clusters in the main catalog, also contains those clusters (with richness $<20$) which have a one-to-one match in the DR8 catalog developed by Wen et al (WHL). We obtain probabilities for cluster membership for each galaxy and implement several procedures for the identification and removal of false cluster detections. We compare our catalog with other SDSS-based ones such as the redMaPPer (26,350 clusters) and the WHL (132,684 clusters) in the same area of the sky and in the overlapping redshift range. We match 97$\%$ of the richest Abell clusters, the same as WHL, while redMaPPer matches $\sim 90\%$ of these clusters. Considering AMF DR9 richness bins, redMaPPer consistently does not possess one-to-one matches for $\sim$20$\%$ AMF DR9 clusters with $Λ_{200}>40$, while WHL matches $\geq$70$\%$ of these missed clusters on average. We also match the AMF catalog with the X-ray cluster catalogs BAX, MCXC and a combined catalog from NORAS and REFLEX. We consistently obtain a greater number of one-to-one matches for X-ray clusters across higher luminosity bins ($L_x>6 \times 10^{44}$ ergs/sec) than redMaPPer while WHL matches the most clusters overall. For the most luminous clusters ($L_x>8$), our catalog performs equivalently to WHL. This new catalog provides a wider sample than redMaPPer while retaining many fewer objects than WHL.