Spectroscopy of the neighboring massive clusters Abell 222 and Abell 223

Abstract

We present a spectroscopic catalog of the neighboring massive clusters Abell 222 and Abell 223. The catalog contains the positions, redshifts, R magnitudes, V - R color, as well as the equivalent widths for a number of lines for 183 galaxies, 153 of them belonging to the A 222 and A 223 system. We determine the heliocentric redshifts to be z = 0.2126 ± 0.0008 for A 222 and z = 0.2079 ± 0.0008 for A 223. The velocity dispersions of both clusters in the cluster restframe are about the same: σ = 1014-71+90 km s-1 and σ = 1032-76+99 km s-1 for A 222 and A 223, respectively. While we find evidence for substructure in the spatial distribution of A 223, no kinematic substructure can be detected. From the red cluster sequence identified in a color-magnitude-diagram we determine the luminosity of both clusters and derive mass-to-light ratios in the R-band of (M/L)A222 = (202 ± 43) h70 M⊙/L⊙ and (M/L)A223 = (149 ± 33) h70 M⊙/L⊙. Additionally we identify a group of background galaxies at z ∼ 0.242.