Abstrak

Kembali

The γ vibration is the most typical low-lying collective motion prevailing in the nuclear chart. But only few one-phonon rotational bands in odd-A nuclei are known. Furthermore, two-phonon states, even the band head, have been observed in a very limited number of nuclides, not only odd- A but also even–even. Among them, that in 105Mo is unique in that Coriolis effects are expected to be stronger than in 103Nb and 105Nb, on which theoretical studies have been reported. The purpose of the present work, then, is to study 105Mo, paying attention to the rotational character change of the one-phonon and two-phonon bands. The particle–vibration coupling model based on the cranking model and the random-phase approximation is used to calculate the vibrational states in rotating odd-A nuclei. The present model reproduces the observed yrast zero-phonon and one-phonon bands well. Emerging general features of the rotational character change from low spin to high spin are elucidated. In particular, the reason why the one-phonon band does not exhibit signature splitting is clarified. The calculated collectivity of the two-phonon states, however, is located higher than observed.