A search for low-lying mixed symmetry states in 140Nd

Abstract

Multipole mixing ratios for transitions between excited 2+ states and the 21+ state in 140Nd are measured using angular correlation techniques for beta decay reactions. Two transitions with dominant Ml components are identified, and the higher-lying 2+ states involved in these transitions are presented as candidates for the one-phonon mixed-symmetric 2+ state in 140Nd. Assuming pure two-state mixing between the one-phonon 2+ state and a presumed three-phonon symmetric state yields a mixing matrix element between these states, which is discussed in terms of shell effects on mixed-symmetric behavior in the N = 80 isotones. Show more