Unveiling a Mysterious Nearby Cool-Core Cluster Lacking a Central BCG

The nearby cluster Abell 1142 is experiencing an offaxis merger between twosubclusters of roughly equal masses. Each subcluster contains a BrightestCluster Galaxy (BCG). Abell 1142 appears to harbor a cool core with a metalabundance gradient declining outward. This cool core is offset from each BCG byvirgul100 kpc. We propose a moderately deep XMM observation of this unique object toobtain its detailed metal distributions in the central region and probe itsglobal gas properties out to 0.5 R_500. The requested observation will enable usto (1) study the enrichment processes of cluster centers (to distinguish betweenthe BCG and the subgroup infall origins) and (2) understand the role of mergersin the formation and destruction of cluster cool cores. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]