The Spin of the 1518 keV Level in¹⁷⁴Yb

Abstract

The spin of the I 518 k e V lecel in li4 Yb.

Structure of two-, four-, and six-quasiparticle isomers inYb174andK-forbidden decays

“…Although we cannot add new spectroscopic information on the decay transitions from the present results except to confirm the mixed multipolarity of the 992-keV transition (see Table I), indirect confirmation of the 6 + assignment comes from the properties of the band established above the isomer. The angular correlation obtained for the 992-keV transition and presented later is essentially identical to that obtained in the early decay work [20], consistent with the assumption of no alignment. Observation of the 7 − intrinsic state, which was not known previously, effectively removes any question of ambiguity.…”

“…This multipolarity, however, cannot be distinguished from the E1/M2 possibility on the basis of the conversion coefficient alone. A γ -γ correlation between the 992-keV transition and the 273-keV 6 + → 4 + transition was claimed [20] to establish a 6 + assignment for the 1518-keV state, but in later measurements it was pointed out by Schmidt, Michelich, and Funk [21] that the angular correlation was also compatible with a 7 − → 6 + → 4 + sequence if E1/M2/E3 multipolarity mixing were considered. They obtained values of E1(68 ± 7%) + M2(5 ± 2%) + E3(27 ± 7%) for that solution, a combination which also reproduces the conversion coefficient.…”