X-Ray Properties of SPT-selected Galaxy Clusters at 0.2

Abstract

© 2019. The American Astronomical Society. All rights reserved. We present measurements of the X-ray observables of the intracluster medium (ICM), including luminosity L X , ICM mass M ICM , emission-weighted mean temperature T X , and integrated pressure Y X , that are derived from XMM-Newton X-ray observations of a Sunyaev-Zel'dovich effect (SZE) selected sample of 59 galaxy clusters from the South Pole Telescope SPT-SZ survey that span the redshift range 0.20 < z < 1.5. We constrain the best-fit power-law scaling relations between X-ray observables, redshift, and halo mass. The halo masses are estimated based on previously published SZE observable-to-mass scaling relations, calibrated using information that includes the halo mass function. Employing SZE-based masses in this sample enables us to constrain these scaling relations for massive galaxy clusters (M 500 ≥ 3 × 10 14 M o ) to the highest redshifts where these clusters exist without concern for X-ray selection biases. We find that the mass trends are steeper than self-similarity in all cases, and with ≥2.5σ significance in the case of L X and M ICM . The redshift trends are consistent with the self-similar expectation, but the uncertainties remain large. Core-included scaling relations tend to have steeper mass trends for L X . There is no convincing evidence for a redshift-dependent mass trend in any observable. The constraints on the amplitudes of the fitted scaling relations are currently limited by the systematic uncertainties on the SZE-based halo masses, but the redshift and mass trends are limited by the X-ray sample size and the measurement uncertainties of the X-ray observables.