High-lying Gamow-Teller excited states in the deformed nuclei, ${}^{76}\text{Ge}$ and ${}^{82}\text{Se}$, by the smearing of the Fermi surface in Deformed Quasi-particle RPA (DQRPA)

Abstract

With the advent of high analysis technology in detecting the Gamow-Teller (GT) excited states beyond one nucleon emission threshold, the quenching of the GT strength to the Ikeda sum rule seems to be recovered by the high-lying GT states. Moreover, in some nuclei, the stronger GT peaks than any other peaks appear explicitly in the high-lying excited states. We address that these high-lying GT excited states stems from the smearing of the Fermi surface by the increase of the chemical potential owing to the deformation within a framework of the deformed quasi-particle random phase approximation (DQRPA). Detailed mechanism leading to the smearing is discussed, and comparisons to the available experimental data are shown to explain the strong peaks on the high-lying GT excited states in a satisfactory manner.

Comments: 8 figures. arXiv admin note: substantial text overlap with arXiv:1205.4561