Alpha Decay of Proton-Rich $^{112}$Cs and $^{111}$Xe

We have performed an experiment at the Holifield Radioactive Ion Beam Facility (Oak Ridge National Laboratory) in an attempt to detect a weak alpha branch in the decay of proton emitter $^{112}$Cs. The ions produced in the fusion-evaporation reaction $^{58}$Ni($^{58}$Ni,p3n)$^{112}$Cs were separated in the Recoil Mass Spectrometer and implanted in a double sided silicon strip detector. We were able to establish an upper limit on the alpha branching ratio of $^{112}$Cs, and to measure the alpha branching ratio of $^{111}$Xe. This work was supported under US DOE grants DE-AC05-00OR22725, DE-FG02-96ER40983, and in part by the NNSA through DOE Cooperative Agreement DE-FC03-03NA00143, the UNIRIB Consortium and the UK STFC.