Abstract
It has been shown experimentally that the Li nucleus shrinks by adding a particle while its spectrum is also compressed. We discuss the compatibility of these two effects, contrasting also with a relation between the shrinkage effect and the stability of the spectrum in the Be hypernucleus. To this end, we employ two-body -He and -He cluster models for the Li and Be hypernuclei, respectively. We first argue that a Gaussian-like interaction between two clusters leads to a stabilization of the spectrum against an addition of a particle, even though the intercluster distance is reduced. In the case of Li, the spin-orbit interaction between the intercluster motion and the deuteron spin has to be considered also. We show that the shrinkage effect makes the expectation value of the spin-orbit potential larger, lowering the excitation energy for the Li( level.
1 More- Received 11 November 2011
DOI:https://doi.org/10.1103/PhysRevC.84.064325
©2011 American Physical Society