SPIN ASSIGNMENTS AND DECAY MODES OF LOW-LYING STATES IN 42SC

A Ge(Li) spectrometer was used in a study of the 40Ca(3He, pγ)42Sc reaction to accurately measure the following excitation energies of low-lying states in 42Sc: 611.5±0.5, 618±2, 1490.8±0.7, 1511±2, 1586.5±0.7, 2188.5±0.9, 2223.0±0.9 and 2270.0±0.9 keV. The previously reported level at 1880 keV was established to be a doublet; the principal decay modes of all the above states were determined. Gamma-ray angular correlations were measured leading to the assignment of spin 1 to the states at 611.5 keV, 2223.0 keV and one member of the doublet at 1880 keV. The spin of the 1490.8 keV state was limited to 2 or 3 and it was further shown that only spin 3 is consistent with the assignment of spin 5 to the 1511 keV state. The ground state of 42Ti has been shown to decay to the 611.5 keV state in 42Sc with a half-life of 0.20±0.02 sec. © 1969.