2023/05/31 by Matthias Klein, Klein, Matthias, D. Hernández-Lang +5 · 2 citations
Engineering · Physics and Astronomy · #Astronomy and Astrophysical Research #CCD and CMOS Imaging Sensors #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #High Energy Astrophysical Phenomena (astro-ph.HE)
paper · pdf · doi:10.48550/arxiv.2305.20066
openalex publication_date 2023/05/31 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present the RASS-MCMF catalog of 8,465 X-ray selected galaxy clusters over 25,000 deg2 of extragalactic sky. The accumulation of deep, multiband optical imaging data, the development of the Multi-Component Matched Filter cluster confirmation algorithm (MCMF), and the release of the DESI Legacy Survey DR10 catalog makes it possible -- for the first time, more than 30 years after the launch of the ROSAT X-ray satellite -- to identify the majority of the galaxy clusters detected in the second ROSAT All-Sky-Survey (RASS) source catalog (2RXS). The resulting 90% pure RASS-MCMF catalog is the largest ICM-selected cluster sample to date. RASS-MCMF probes a large dynamic range in cluster mass spanning from galaxy groups to the most massive clusters. The cluster redshift distribution peaks at z∼0.1 and extends to redshifts z∼1. Out to z∼0.4, the RASS-MCMF sample contains more clusters per redshift interval (dN/dz) than any other ICM-selected sample. In addition to the main sample, we present two subsamples with 6,924 and 5,516 clusters, exhibiting 95% and 99% purity, respectively.. We forecast the utility of the sample for a cluster cosmological study, using realistic mock catalogs that incorporate most observational effects, including the X-ray exposure time and background variations, the existence likelihood selection and the impact of the optical cleaning with the algorithm MCMF. Using realistic priors on the observable-mass relation parameters from a DES-based weak lensing analysis, we estimate the constraining power of the RASS-MCMF×DES sample to be of 0.026, 0.033 and 0.15 (1σ) on the parameters Ωm, σ8 and w, respectively.