2015/04/20 by H. Mei, Mei, H., K. Hagino +5
Physics and Astronomy · #FOS: Physical sciences #Nuclear Experiment (nucl-ex) #Nuclear Theory (nucl-th) #Nuclear physics research studies #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #nucl-ex #nucl-th
paper · pdf · doi:10.48550/arxiv.1504.04924
18 pages, 20 eps figures
arxiv created 2015/04/20 · openalex publication_date 2015/04/20 · arxiv updated 2015/04/21 · openalex created_date 2024/04/11 · openalex updated_date 2026/07/28
We present a detailed formalism of the microscopic particle-rotor model for hypernuclear low-lying states based on a covariant density functional theory. In this method, the hypernuclear states are constructed by coupling a hyperon to low-lying states of the core nucleus, which are described by the generator coordinate method (GCM) with the particle number and angular momentum projections. We apply this method to study in detail the low-lying spectrum of 13~ΛC and 21~ΛNe hypernuclei. We also briefly discuss the structure of 155~~ΛSm as an example of heavy deformed hypernuclei. It is shown that the low-lying excitation spectrum with positive parity states of the hypernuclei, which are dominated by Λ hyperon in s-orbital coupled to the core states, are similar to that for the corresponding core states, while the electric quadrupole transition strength, B(E2), from the 2+1 state to the ground state is reduced according to the mass number of the hypernuclei. Our study indicates that the energy splitting between the first 1/2- and 3/2- hypernuclear states is generally small for all the hypernuclei which we study. However, their configurations depend much on the properties of a core nucleus, in particular on the sign of deformation parameter. That is, the first 1/2- and 3/2- states in 13~ΛC are dominated by a single configuration with Λ particle in the p-wave orbits and thus providing good candidates for a study of the Λ spin-orbit splitting. On the other hand, those states in the other hypernuclei exhibit a large configuration mixing and thus their energy difference cannot be interpreted as the spin-orbit splitting for the p-orbits.