Decay ofSm155

Abstract

${\mathrm{Sm}}^{155}$ was found to decay to ${\mathrm{Eu}}^{155}$ with a half-life of 21.9±0.2 minutes. Internal conversion electrons corresponding to the gamma rays in ${\mathrm{Eu}}^{155}$ were observed in a magnetic spectrometer. The gamma ray spectrum was studied with a well crystal. The spectra of gamma rays coincident with the x ray, 104-kev, 142-kev, and 246-kev gamma rays were observed. A number of new, weak transitions are proposed. Directional correlation measurements were made on the 142-kev—104-kev cascade. Possible spin assignments are discussed.