We present results from a 100 ks XMM- Newton observation of galaxy cluster XLSSC 122 , the first massive cluster discovered through its X-ray emission at z \approx 2 .
The data provide the first precise constraints on the bulk thermodynamic properties of such a distant cluster , as well as an X-ray spectroscopic confirmation of its redshift .
We measure an average temperature of kT = 5.0 \pm 0.7 keV ; a metallicity with respect to solar of Z / Z _ { \odot } = 0.33 ^ { +0.19 } _ { -0.17 } , consistent with lower-redshift clusters ; and a redshift of z = 1.99 ^ { +0.07 } _ { -0.06 } , consistent with the earlier photo- z estimate .
The measured gas density profile leads to a mass estimate at r _ { 500 } of M _ { 500 } = ( 6.3 \pm 1.5 ) \times 10 ^ { 13 } M _ { \odot } .
From CARMA 30 GHz data , we measure the spherically integrated Compton parameter within r _ { 500 } to be Y _ { 500 } = ( 3.6 \pm 0.4 ) \times 10 ^ { -12 } .
We compare the measured properties of XLSSC 122 to lower-redshift cluster samples , and find good agreement when assuming the simplest ( self-similar ) form for the evolution of cluster scaling relations .
While a single cluster provides limited information , this result suggests that the evolution of the intracluster medium in the most massive , well developed clusters is remarkably simple , even out to the highest redshifts where they have been found .
At the same time , our data reaffirm the previously reported spatial offset between the centers of the X-ray and SZ signals for XLSSC 122 , suggesting a disturbed configuration .
Higher spatial resolution data could thus provide greater insights into the internal dynamics of this system .