Description
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_<2.4x10_70_^-1^M_{sun}_, L<2x10^44^erg/s, 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_<21.9x10^14^M_{sun}_, 0.15<=z<=0.55) from the Canadian Cluster Comparison Project finds that within r_2500_, M{prop.to}L^0.44+/-0.05^, T{prop.to}L^0.23+/-0.02^, and M{prop.to}T^1.9+/-0.2^. The estimated intrinsic scatter in the M-L relation for the combined sample is reduced to {sigma}_log(M|L)_=0.10, from {sigma}_log(M|L)_=0.26 with the original ROSAT measurements. We also find an intrinsic scatter for the T-L relation, {sigma}_log(T|L)_=0.07+/-0.01.
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