Clusters of galaxies up to z=1.5 identified from photometric data of the Dark Energy Survey and unWISE

Understand

Using photometric data from the Dark Energy Survey and the Wide-field Infrared Survey Explorer, we estimate photometric redshifts for 105 million galaxies using the nearest-neighbour algorithm.

• From such a large data base, 151,244 clusters of galaxies are identified in the redshift range of 0.1<z<1.5 based on the overdensity of the total stellar mass of galaxies within a given photometric redshift slice, among which 76,826 clusters are newly identified and 30,477 clusters have a redshift z>1.
• We cross-match these clusters with those in the catalogues identified from the X-ray surveys and the Sunyaev--Zel'dovich (SZ) effect by the Planck, South Pole Telescope and Atacama Cosmology Telescope surveys, and get the redshifts for 45 X-ray clusters and 56 SZ clusters.
• More than 95 percent SZ clusters in the sky region have counterparts in our catalogue.