Cluster states in B

Abstract

The excited states of 13B were studied by a method of antisymmetrized molecular dynam3 ics (AMD). In the excited states, we predicted many cluster states with large deformations that construct the rotational bands, Kπ - 3/2- and Kπ = 1/2+, starting from 5 and 8 MeV, respectively. The neutron structure of the K π = 3/2- band is analogous to the 12Be ground state with a 2hωw configuration. The Kπ = 3/2 --band members correspond to the experimental level at 10.22 MeV, which is suggested to be a high-spin state with the 2hω configuration. In the predicted Kπ = 1/2+ band, we found a very exotic molecular structure with a larger deformation than superdeformation. This largely deformed state is dominated by a 3hω configuration with one proton and two neutrons in the sd shell. In highly excited states, well-developed 9Li + α cluster structures were predicted.