Three-body model study of {ital A}=6{endash}7 hypernuclei: Halo and skin structures
- Department of Physics, Kyushu University, Fukuoka 812 (Japan)
- Laboratory of Physics, Osaka Electro-Communication University, Neyagawa, Osaka 572 (Japan)
- Laboratory of Physics, Kanto Gakuin University, Yokohama 236 (Japan)
- Physics Section, Tsuru University, Tsuru, Yamanashi 402 (Japan)
Low-lying states of {ital A}=6 hypernuclear doublets ({sub {Lambda}}{sup 6}He and {sub {Lambda}}{sup 6}Li) and {ital A}=7 triplets ({sub {Lambda}}{sup 7}He, {sub {Lambda}}{sup 7}Li, and {sub {Lambda}}{sup 7}Be) are studied with an accurate three-body model calculation in which all the rearrangement Jacobian coordinates are equally taken into account. Since most of the hypernuclear states concerned are weakly bound states, focus is placed on the binding energies with respect to the particle breakup thresholds and on the density distributions in the surface and exterior regions. With the {alpha}+{Lambda}+{ital N} model, the observed binding energies of the ground states of {sub {Lambda}}{sup 6}He and {sub {Lambda}}{sup 6}Li are well reproduced. {sub {Lambda}}{sup 6}He is found to have a three-layer structure of the matter distribution: the {alpha} nuclear core, a {Lambda} skin, and a neutron halo. The {ital A}=7 hypernuclei are shown to be well described with the {sub {Lambda}}{sup 5}He + {ital N}+{ital N} model. Using a realistic {ital NN} interaction, the correlation between the valence nucleons is fully taken into account; this is essentially important to make the {ital proton}-{ital rich} three-body system {sub {Lambda}}{sup 7}Be = {sub {Lambda}}{sup 5}He + {ital p}+{ital p} bound although none of the two-body subsystems is bound. The observed binding energies of {sub {Lambda}}{sup 7}Li and {sub {Lambda}}{sup 7}Be are well reproduced, and energies are predicted for {sub {Lambda}}{sup 7}He whose core nucleus is a neutron halo nucleus, {sup 6}He. We discuss the validity of the assumption of frozen deuterons adopted in the previous {alpha}+{ital d}+{Lambda} models for the {ital T}=0 states of {sub {Lambda}}{sup 7}Li. {copyright} {ital 1996 The American Physical Society.}
- OSTI ID:
- 283946
- Journal Information:
- Physical Review, C, Journal Name: Physical Review, C Journal Issue: 5 Vol. 53; ISSN 0556-2813; ISSN PRVCAN
- Country of Publication:
- United States
- Language:
- English
Similar Records
Three- and four-body structure of S = -2 hypernuclei
Double hypernuclei and the $lambda$$lambda$ interaction