New measurements of radial velocities in clusters of galaxies -- V

TL;DR

This paper reports new radial velocity measurements for galaxies in four clusters, refining their properties and clarifying cluster memberships, contributing to the understanding of galaxy cluster dynamics and large-scale structure.

Contribution

Provides 80 new galaxy velocities in four clusters, clarifies cluster memberships, and refines cluster redshifts and velocity dispersions, enhancing galaxy cluster data.

Findings

A376 has <z>=0.047503 and _V=860 km/s

A970 has <z>=0.058747 and _V=881 km/s

A1356 is a foreground group, not part of Leo-Virgo supercluster

Abstract

As a part of our galaxy-cluster redshift survey, we present a set of 80 new velocities in the 4 clusters Abell 376, Abell 970, Abell 1356, and Abell 2244, obtained at Haute-Provence observatory. This set now completes our previous analysis, especially for the first two clusters. Data on individual galaxies are presented, and we discuss some cluster properties. For A376, we obtained an improved mean redshift <z> = 0.047503$ with a velocity dispersion of \sigma_V = 860 km/s. For A970, we have <z> = 0.058747 with \sigma_V = 881 km/s. We show that the A1356 cluster is not a member of the "Leo-Virgo" supercluster at a mean redshift <z>= 0.112 and should be considered just as a foreground group of galaxies at <z> = 0.0689, as well as A1435 at <z> = 0.062. We obtain <z> = 0.099623 for A2244 with \sigma_V = 965 km/s. The relative proximity of clusters A2244 and A2245 (<z> = 0.0873816, \sigma_V = 992 km/s) suggests that these could be members of a supercluster that would include A2249; however, from X-ray data there is no indication of interaction between A2244 and A2245.