Polarization charges and electric quadrupole transitions of yrast terminating bands inTi44,46,48

Abstract

The polarization charges in $^{44,46,48}\mathrm{Ti}$ are studied by the microscopic particle-vibration model and used to investigate the electric quadrupole transitions of the yrast terminating bands. The validity of the commonly used empirical effective charges in the $\mathit{pf}$ shell-model calculations is confirmed. The quadrupole transition probabilities $B(E2,I\ensuremath{\rightarrow}I\ensuremath{-}2)$ and electromagnetic moments are reasonably well reproduced compared with experimental results. It is found that a globally decreasing $B(E2)$ is accompanied with convergence of valence particles into the $1{f}_{7/2}$ shell when approaching the terminating states. The $I={6}^{+}$ state in $^{48}\mathrm{Ti}$ shows an exotic behavior with an irregularity of $B(E2)$ and sign change of electromagnetic moments, which is related to a neutron-dominant prolate shape.