XMM-Newton Observations of New Massive Planck Clusters

Through a program of groundbased optical and nearinfrared imaging begun thisyear, we have identified a number of rich, massive clusters among theunconfirmed Planck cluster candidates. We have selected the five most promisingnew clusters for observation with XMM this cycle. All have Plancksignaltonoise ratios greater than 5.2 and significant RASS Xray flux. Theproposed observations will provide the first accurate masses of these clustersbased on multiple Xray mass proxies and will allow determination of theirdynamical states (merger vs. relaxed systems). truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]