SPIDERS: An Overview of The Largest Catalogue of Spectroscopically Confirmed X-ray Galaxy Clusters

TL;DR

SPIDERS provides the largest spectroscopically confirmed X-ray galaxy cluster catalog, improving cluster identification accuracy and offering new cosmological insights through detailed analysis of redshifts and velocity dispersions.

Contribution

This paper presents a comprehensive catalog of 2740 spectroscopically confirmed X-ray galaxy clusters from SDSS-IV, including validation methods, performance metrics, and updated scaling relations.

Findings

Over 99% validation success for clusters with sufficient redshifts

Significant improvement in redshift accuracy over other surveys

New cosmological constraints from velocity dispersion analysis

Abstract

SPIDERS is the spectroscopic follow-up effort of the Sloan Digital Sky Survey IV (SDSS-IV) project for the identification of X-ray selected galaxy clusters. We present our catalogue of 2740 visually inspected galaxy clusters as a part of the SDSS Data Release 16 (DR16). Here we detail the target selection, our methods for validation of the candidate clusters, performance of the survey, the construction of the final sample, and a full description of what is found in the catalogue. Of the sample, the median number of members per cluster is approximately 10, with 818 having 15 or greater. We find that we are capable of validating over 99% of clusters when 5 redshifts are obtained below $z<0.3$ and when 9 redshifts are obtained above $z>0.3$. We discuss the improvements of this catalogue's identification of cluster using 33,340 redshifts, with $\Delta z_{\rm{phot}} / \Delta z_{\rm{spec}} \sim 100$, over other photometric and spectroscopic surveys, as well as present an update to previous ($\sigma - L_{X}$) and ($\sigma - \lambda$) relations. Finally, we present our cosmological constraints derived using the velocity dispersion function.