PKS B1400-33 and Abell S753: A Very Bright Radio Relic in a Poor Cluster

The cluster radio relic PKS B140033 in the poor cluster Abell S753 will beobserved with XMM/Newton and NuSTAR to detect and image the nonthermal InverseCompton emission. This is the second brightest cluster radio relic known.Remarkably, it is associated with a relatively poor, cool cluster. Although ithas many properties similar to other cluster radio relics, it is possible thatit is an old radio lobe, displaced by motions or buoyancy. These observationswill be a strong test of merger shock acceleration processes, and will give themagnetic field, nonthermal energy, and shock acceleration efficiency. Theobservations will allow the dynamical state of the cluster to be determined, andwill detect the merger shock which is expected to be associated with the relic. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]