Shape coexistence in neutron-deficient Hg isotopes studied via lifetime measurements in ${}^{184,186}$Hg and two-state mixing calculations

Abstract

The neutron-deficient mercury isotopes, ${}^{184,186}$Hg, were studied with the Recoil Distance Doppler Shift (RDDS) method using the Gammasphere array and the Köln Plunger device. The Differential Decay Curve Method (DDCM) was employed to determine the lifetimes of the yrast states in ${}^{184,186}$Hg. An improvement on previously measured values of yrast states up to $8^{+}$ is presented as well as first values for the $9_3$ state in ${}^{184}$Hg and $10^{+}$ state in ${}^{186}$Hg. $B(E2)$ values are calculated and compared to a two-state mixing model which utilizes the variable moment of inertia (VMI) model, allowing for extraction of spin-dependent mixing strengths and amplitudes.

8 pages, 9 figures, 2 tables