Decay of yttrium-87

Abstract

The decay of 80 h ⁸⁷Y produced by proton bombardment of natural strontium has been investigated by means of a Ge(Li) detector in singles and in coincidence with a NaI detector. Gamma-rays of energy 388 and 487 keV with relative intensities of 95 and 100, respectively, have been observed. Coincidence data suggest levels in ⁸⁷Sr at 388 and 875 keV. The logft values for transition to these levels are, respectively, 7.1±0.3 and 5.2±0.3. The 1.22 MeV level seen in nuclear-reaction studies is not populated in the decay of ⁸⁷Y (logft >9.8). The half-life of the isomeric level of ⁸⁷Sr at 388 keV has been accurately determined to be (169.8±0.6) min.