Proton Decay of the Isobaric Analog of the Ground State ofPb208Populated by the (p,n) Reaction

Abstract

The relative widths for the proton ($\tilde{p}$) decay of the isobaric analog of the ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$ ground state have been remeasured with significantly improved accuracy using the charge-exchange reaction ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}\mathrm{}(p,n)\mathrm{}$ rather than ${}_{}{}^{207}{}_{}{}^{}\mathrm{Pb}\mathrm{}(p,p)\mathrm{}$ and ($p,p^{\prime }$) excitation functions to populate the isobaric analog level. For the first time the sequential process ($p,n\tilde{p}$) has been observed both with a heavy ($A\sim 200$) target nucleus and also with a target nucleus which is even-even rather than even-odd. The total cross section for the isobaric-analog-state reaction ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}\mathrm{}(p,n)\mathrm{}{}_{}{}^{208}{}_{}{}^{}\mathrm{Bi}$ has also been measured for the range of proton bombarding energies between 25.2 and 47.3 MeV.