Scaling Relations and X-Ray Properties of Moderate-luminosity Galaxy Clusters from 0.3 < z < 0.6 with XMM-Newton

Abstract

We present new X-ray temperatures and improved X-ray luminosity estimates for 15 new and archival XMM-Newton observations of galaxy clusters at intermediate redshift with mass and luminosities near the galaxy group/cluster division ({M}₂₅₀₀ < 2.4 × 10¹⁴ h₇₀^-1 {M}_⊙, L < 2 × 10⁴⁴ erg s^-1, 0.3 < z < 0.6). These clusters have weak-lensing mass measurements based on Hubble Space Telescope observations of clusters representative of an X-ray-selected sample (the ROSAT 160SD survey). The angular resolution of XMM-Newton allows us to disentangle the emission of these galaxy clusters from nearby point sources, which significantly contaminated previous X-ray luminosity estimates for 6 of the 15 clusters. We extend cluster scaling relations between X-ray luminosity, temperature, and weak-lensing mass for low-mass, X-ray-selected clusters out to redshift ~0.45. These relations are important for cosmology and the astrophysics of feedback in galaxy groups and clusters. Our joint analysis with a sample of 50 clusters in a similar redshift range but with larger masses (M ₅₀₀ < 21.9 × 10¹⁴ M _⊙, 0.15 <= z <= 0.55) from the Canadian Cluster Comparison Project finds that within r ₂₅₀₀, MvpropL ^{0.44 ± 0.05}, TvpropL ^{0.23 ± 0.02}, and MvpropT ^{1.9 ± 0.2}. The estimated intrinsic scatter in the M-L relation for the combined sample is reduced to σ_{log (M|L)} = 0.10, from σ_{log (M|L)} = 0.26 with the original ROSAT measurements. We also find an intrinsic scatter for the T-L relation, σ_{log (T|L)} = 0.07 ± 0.01.

Based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA.