A catalog of 1.58 million clusters of galaxies identified from the DESI Legacy Imaging Surveys

TL;DR

This paper presents a comprehensive catalog of 1.58 million galaxy clusters identified from DESI Legacy Imaging Surveys, including many new detections, with detailed properties and evolutionary insights.

Contribution

It provides the largest galaxy cluster catalog to date from DESI data, including new clusters and detailed dynamical and stellar mass analyses.

Findings

Identified 1.58 million clusters, with 877,806 new detections.

Most clusters match previous optical, SZ, and X-ray catalogs.

Brightest cluster galaxies' stellar mass doubles since z=1.

Abstract

Based on the DESI Legacy Imaging Surveys released data and available spectroscopic redshifts, we identify 1.58 million clusters of galaxies by searching for the overdensity of stellar mass distribution of galaxies within redshift slices around pre-selected massive galaxies, among which 877,806 clusters are found for the first time. The identified clusters have an equivalent mass of M_{500}> 0.47*10^{14}~Msolar with an uncertainty of 0.2 dex. The redshift distribution of clusters extends to z~1.5, and 338,841 clusters have spectroscopic redshifts. Our cluster sample includes most of the rich optical clusters in previous catalogs, more than 95% massive Sunyaev-Zeldovich clusters and 90% ROSAT and eROSITA X-ray clusters. From the light distributions of member galaxies, we derive the dynamical state parameters for 28,038 rich clusters and find no significant evolution of the dynamical state with redshift. We find that the stellar mass of the brightest cluster galaxies grows by a factor of 2 since z=1.