Deep XMM-Newton observations of the most distant SPT-SZ galaxy cluster

We present results from a 577 ks XMM-Newton observation of SPT-CLJ0459-4947, the most distant cluster detected in the South Pole Telescope 2500 square degree (SPT-SZ) survey, and currently the most distant cluster discovered through its Sunyaev-Zerdovich effect. The data confirm the cluster's high redshift, z = 1.71 +/- 0.02, in agreement with earlier, less precise optical/IR photometric estimates. From the gas density profile, we estimate a characteristic mass of M-500 = (1.8 +/- 0.2) x 10(14) M-circle dot; cluster emission is detected above the background to a radius of similar to 2.2 r(500), or approximately the virial radius. The intracluster gas is characterized by an emission-weighted average temperature of 7.2 +/- 0.3 keV and metallicity with respect to Solar of Z/ Z(circle dot) = 0.37 +/- 0.08. For the first time at such high redshift, this deep data set provides a measurement of metallicity outside the cluster centre; at radii r > 0.3 r(500), we find Z/ Z(circle dot) = 0.33 +/- 0.17 in good agreement with precise measurements at similar radii in the most nearby clusters, supporting an early enrichment scenario in which the bulk of the cluster gas is enriched to a universal metallicity prior to cluster formation, with little to no evolution thereafter. The leverage provided by the high redshift of this cluster tightens by a factor of 2 constraints on evolving metallicity models, when combined with previous measurements at lower redshifts.