Proton emission from the drip line nucleus ${}_{63}^{131}\mathrm{Eu},$ to the first excited $2^{+}$ state of the daughter nucleus ${}_{62}^{130}\mathrm{Sm}$ is analyzed as decay from a deformed nucleus, and the half-lives are evaluated exactly. It is found that the Nilsson state ${K=3/2\mathrm{}}^{+}$ for a deformation $0.34>\mathrm{}\beta >0.27\mathrm{}$ describes both the fine structure and the decay to the ground state of ${}^{130}\mathrm{Sm}.$

• Received 1 December 1999

DOI:https://doi.org/10.1103/PhysRevC.61.047307