High spin rotational bands in 70As nucleus

Abstract

Structures of the high spin states in the odd-odd nucleus 70As have been investigated following two heavy-ion fusion evaporation reactions 51V(28Si, 2αn) and 46Ti(28Si, 3pn). Seventeen new transitions have been found and placed in the level scheme of 70As. The onset of collectivity is observed at high spin with the discovery of three rotational bands, similar to 72As. The kinematic moments of inertia of these bands follow the general systematics of mass 70 region. The π [440]1/2+ ⊗ v [431]3/2+ and π [301]3/2- ⊗® v [431]3/2+ configurations are proposed for +ve and -ve parity bands, respectively. The finding of quite different signature splitting for +ve parity bands in 70As and 72As is interpreted as due to different shapes of these nuclei from the Total Routhian Surface (TRS) calculations.