Limits of observable proton-emitting nuclei between the N=82 and Z=82 shell closures

The regular systematic behavior of Q(p) values is analyzed to provide a basis for estimating Q values for as yet unknown proton and alpha decays. These estimates are used in predicting partial half-lives for proton and alpha-particle emission from states in Ta, Re, Ir, and Au nuclei beyond the proton drip line. The implications of these predictions for further experimental study in this region are discussed.