A new proton emission line has been observed in the nucleus ${}_{}{}^{156}{}_{}{}^{}\mathrm{Ta}$ using the fusion reaction ${}_{}{}^{58}{}_{}{}^{}\mathrm{Ni}$${+}^{102}$Pd${\to }^{160}$${\mathrm{W}}^{\mathrm{*}}$, ${\mathit{E}}_{\mathit{x}}$≃61 MeV. The line has a proton energy ${\mathit{E}}_{\mathit{p}}$=1103±12 keV corresponding to a Q value ${\mathit{Q}}_{\mathit{p}}$=1110±12 keV, and a half-life of 320±80 ms. The proton line is assigned to a ∼3% decay branch from a high spin π${\mathit{h}}_{11/2}$ν${\mathit{f}}_{7/2}$ isomeric state on the basis of systematics. The subsequent implications for level ordering in this region beyond the proton drip line are discussed.

• Received 15 July 1993

DOI:https://doi.org/10.1103/PhysRevC.48.R2151