LoCuSS: hydrostatic mass measurements of the high-L_X cluster sample - cross-calibration of Chandra and XMM-Newton

We present a consistent analysis of Chandra and XMM–Newton observations of an approximately mass-selected sample of 50 galaxy clusters at 0.15 < z < 0.3 – the ‘LoCuSS high-L_X sample’. We apply the same analysis methods to data from both satellites, including newly developed analytic background models that predict the spatial variation of the Chandra and XMM–Newton backgrounds to <2 and <5 per cent precision, respectively. To verify the cross-calibration of Chandra- and XMM–Newton-based cluster mass measurements, we derive the mass profiles of the 21 clusters that have been observed with both satellites, extracting surface brightness and temperature profiles from identical regions of the respective data sets. We obtain consistent results for the gas and total hydrostatic cluster masses: the average ratio of Chandra- to XMM–Newton-based measurements of M_gas and M_X at r₅₀₀ are 0.99 ± 0.02 and 1.02 ± 0.05, respectively, with an intrinsic scatter of ∼3 per cent for gas masses and ∼8 per cent for hydrostatic masses. Comparison of our hydrostatic mass measurements at r₅₀₀ with the latest Local Cluster Substructure Survey (LoCuSS) weak-lensing results indicate that the data are consistent with non-thermal pressure support at this radius of ∼7 per cent. We also investigate the scaling relation between our hydrostatic cluster masses and published integrated Compton parameter Y_sph measurements from the Sunyaev–Zel'dovich Array. We measure a scatter in mass at fixed Y_sph of ∼16 per cent at Δ = 500, which is consistent with theoretical predictions of ∼10–15 per cent scatter.