6533b7dafe1ef96bd126f456

RESEARCH PRODUCT

Proton radioactivity of117La

subject

description

A new more precise measurement of the ground-state proton decay of ${}^{117}\mathrm{La}$ is presented $[{E}_{p}=806(5) \mathrm{keV},$ ${t}_{1/2,p}=26(3)$ ms]. ${}^{117}\mathrm{La}$ was produced via the $p4n$ fusion-evaporation channel by bombarding a ${}^{64}\mathrm{Zn}$ target with 310 and 295 MeV ${}^{58}\mathrm{Ni}$ beams. The proton decay rate is consistent with emission from a prolate deformed ${3/2}^{+}$ or ${3/2}^{\ensuremath{-}}$ Nilsson state. No evidence is found for a previously reported proton decay from a high spin isomer in ${}^{117}\mathrm{La}.$ An upper limit for the production cross section for proton decay of ${}^{116}\mathrm{La}$ at a bombarding energy of 325 MeV was established.