Improved measurement of the 0(2)(+) -> 0(1)(+) E0 transition strength for Se-72 using the SPICE spectrometer

AbstraktAbstract

The selenium isotopes lie at the heart of a tumultuous region of the nuclear chart where shape coexistence effects grapple with neutron-proton pairing correlations, triaxiality, and the impending proton drip line. In this work, a study of Se-72 by internal conversion electron and gamma-ray spectroscopy was undertaken with the SPICE and TIGRESS arrays. New measurements of the branching ratio and lifetime of the 0(2)(+) state were performed, yielding a determination of rho(2)(E-0; 0(2)(+) -> 0(1)(+))- = 29(3) milliunits. Two-state mixing calculations were performed that highlighted the importance of interpretation of such E0 strength values in the context of shape coexistence.

The selenium isotopes lie at the heart of a tumultuous region of the nuclear chart where shape coexistence effects grapple with neutron-proton pairing correlations, triaxiality, and the impending proton drip line. In this work, a study of Se-72 by internal conversion electron and gamma-ray spectroscopy was undertaken with the SPICE and TIGRESS arrays. New measurements of the branching ratio and lifetime of the 0(2)(+) state were performed, yielding a determination of rho(2)(E-0; 0(2)(+) -> 0(1)(+))- = 29(3) milliunits. Two-state mixing calculations were performed that highlighted the importance of interpretation of such E0 strength values in the context of shape coexistence.