Resolving the puzzling dynamical status of the rotating cluster Abell 2107

Current studies on the dynamics of the Intra Cluster Medium are based onspatially resolved, modest spectral resolution CCD data, focused mostly on bulkmotions associated to major mergers. Here we propose a deep XMM observation ofthe cluster Abell 2107, which is so far the only candidate cluster with arotating ICM as found by our group on the basis of shallow Chandra Xray data.The unique combination of high efficiency RGS and spatially resolved, high S/N,accurately calibrated, EPIC data is the only way to solve the puzzling dynamicalstatus of A2107. In particular, we propose an angleconstrained observation withgrating dispersion along to the rotation axis range to firmly confirm ordisprove the ICM rotation. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]