094083

We have recently discovered a massive cool core cluster at the epoch of clusterformation (z=1.709 SpARCS1049). Using deep Chandra data we found that the coolcore is catastrophically cooling with no AGN feedback from the central galaxy.The hot intracluster gas is thus fuelling a massive burst of star formation(860+/-130 M_sun/yr) marking the first cooling flow without AGN feedback. Wepropose deep (526 ks) XMM observations to: 1) detect cooling flow spectralsignatures 2) map for the first time metallicity in a z>1 cool core cluster 3)explore the assembling outer halo of the intracluster gas and self-similarstatus. These observations will play a crucial role in understanding thetransition of massive structures from proto-clusters to galaxy clusters [truncated! Please see actual data for full text]