Structure of Λ10Be studied with the four-body cluster model

Energy levels of the hypernucleus Be-10(Lambda) within the framework of alpha + alpha + Lambda + n four-body cluster model are calculated. Interactions between the constituent subunits are determined so as to reproduce reasonably well the observed low-energy properties of the alpha alpha, alpha N, alpha Lambda, alpha alpha Lambda and alpha alpha N subsystems. Furthermore, the two-body Lambda N interaction is adjusted so as to reproduce the 0(+)-1(+) splitting of H-4(Lambda). The Lambda separation energies of positive parity states are smaller than those of negative parity states. As a result, there occurs level inversion between 0(+), 1(1)(+) states and 3 and 2(2)(-) states. (C) 2012 Elsevier B.V. All rights reserved.