XMM-Newton Observation of the Cluster Zw 1305.4+2941 in the Field SA 57

Abstract

We report the details of an XMM-Newton observation of the cluster of galaxies Zw 1305.4+2941 at the intermediate redshift z = 0.241, increasing the small number of interesting X-ray constraints on properties of ~3 keV systems above z = 0.1. Based on the ~45 ks XMM-Newton observation, we find that within a radius of 228 kpc the cluster has an unabsorbed X-ray flux of f_X = (2.07 +/- 0.06) × 10^-13 ergs cm^-2 s^-1, a temperature of kT = 3.17 +/- 0.19 keV, in good agreement with the previous ROSAT determination, and an abundance of 0.93^{+ 0.24}_-0.29 Z_⊙. Within r₅₀₀ = 723 +/- 16 kpc the rest-frame bolometric X-ray luminosity is L_X(r₅₀₀) = (1.25 +/- 0.16) × 10⁴⁴ h^-2₇₀ ergs s^-1. The cluster obeys the scaling relations for L_X, T, and the velocity dispersion σ_v derived at intermediate redshift for kTlesssim 4 keV, for which we provide new fits for all objects in the literature. The mass derived from an isothermal NFW model fit is M_vir = (2.77 +/- 0.21) × 10¹⁴ M_⊙, with the concentration parameter c = 7.9 +/- 0.5.