First Measurement Of Proton Decay From A Transfer Reaction To Na-21

Decay protons from excited states in Na-21 populated through a previously reported Mg-24(p, alpha) Na-21 transfer reaction [Cha et al., Phys. Rev. C 96, 025810 (2017)] were analyzed to extract the proton branching ratios of the energy levels. By utilizing 31-MeV proton beams from the Holifield Radioactive Ion Beam Facility of Oak Ridge National Laboratory and isotopically enriched Mg-24 solid targets, the decay protons were detected in coincidence with alpha particles from the (p, alpha) reaction using a silicon strip detector array. Proton decay branching ratios of several Na-21 levels were deduced for the p0 and p1 decay channels to the ground and first excited states in Ne-20, respectively.