On three-cluster resonance structure of hypernuclei ${}_{\Lambda }^7$He, ${}_{\Lambda }^7$Li and ${}_{\Lambda }^7$Be

Abstract

The bound and resonance states of hypernuclei ${}_{\Lambda }^7$He, ${}_{\Lambda }^7$Li and ${}_{\Lambda }^7$Be are studied within a three-cluster model. Within this model, hypernuclei ${}_{\Lambda }^7$He, ${}_{\Lambda }^7$Li and ${}_{\Lambda }^7$Be are considered as three-cluster systems ${}^4$He+${}^{2}n$+$\Lambda$, ${}^4$He+$d$+$\Lambda$, ${}^4$He+${}^{2}p$+$\Lambda$, respectively. Special attention is paid to determining resonance states in the three-cluster continuum of these hypernuclei and to study their nature. One semi-realistic nucleon-nucleon potential is employed to determine the internal structure of the clusters ${}^4$He, ${}^{2}n$, $d$ and ${}^{2}p$, and their interaction. Three versions of the nucleon-hyperon potential, known as the YNG potential, are employed to determine the interaction of the listed clusters with the lambda hyperon. A set of very narrow and fairly wide resonance states is found in the three-cluster continuum of ${}_{\Lambda }^7$He, ${}_{\Lambda }^7$Li and ${}_{\Lambda }^7$Be. The narrowest resonance states were detected in ${}_{\Lambda }^7$He and ${}_{\Lambda }^7$Li and their total width does not exceed 10 keV. The dominant decay channels of these resonance states are revealed.

Comments: 53 pages, 21 figures, 16 tables, typos corrected