X-Ray Properties of SPT-selected Galaxy Clusters at 0.2 < z < 1.5 Observed with XMM-Newton

Abstract

We present measurements of the X-ray observables of the intra-cluster 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 of 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 ) 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, however the redshift and mass trends are limited by the X-ray sample size and the measurement uncertainties of the X-ray observables. −0.16 7 3 0.28 +0.07 −0.09 0.02 +0.48 −0.58 0.76 +0.76 −0.71 III with fixed SZE params 9.93 +0.58 −0.49 1.90 +0.13 −0.18 7 3 0.25 +0.07 −0.06 −0.18 +0.48 −0.32 0.80 +0.93 −0.57

Cosmology dependence of galaxy cluster scaling relations

“…Mantz et al 2016, B19). We find a log-normal scatter of 11%, consistent (within 2-σ) with the observed scatter in Tgas -M500c relation (Bulbul et al 2019).…”

“…While residual trends and variations in these parameters are clearly visible (e.g., decreasing α for Mgas from C1 to C15), we note that these differences are much smaller than current state-of-the-art observational constraints (lighter grey bands enclosed by dashed lines in Figure 2) for the three X-ray observables Bulbul et al (2019) (hereafter, B19) and by previous studies on simulations for the σv-M relation (Evrard et al 2008). This result therefore justifies our assumption about the cosmology independence of α, β and σ in Equation 1.…”

“…Results of the fitting procedure for the core-subtracted luminosity are shown in Table A1. There is a minor deviation from the self-similar mass slope compared to the observed core-subtracted L X,bol − M 500c relation (Bulbul et al 2019). Note that the observations are made at a different overdensity and a different definition of core radius.…”

“…Most of the X-ray luminosity is associated to the central cluster regions, as L bol is proportional to the density square. For this reason, it is much more strongly affected by relatively small scale physical processes such as cooling and feedback, which are not naturally accounted by the self-similar prediction (Pratt et al 2009;Bulbul et al 2019).…”

“…While here we extend to virial Figure 1 with the same color scheme. The lighter grey bands enclosed by dashed lines represent current state-of-the-art observational uncertainties on the three X-ray observables (Bulbul et al 2019), while the uncertainty on σv-M relation is the result of previous simulation studies (Evrard et al 2008). Empty squares correspond to non-radiative runs (performed for C1 and C15) whereas empty circles correspond to the simulation run with a different feedback scheme for C8 cosmology.…”