Final-state interactions in the decay of the hypernucleus Λ9Li and a reappraisal of the binding energies of A=9 hypernuclei

Abstract

The Λ 9 Li→π −+ 9 Be ∗→π −+ p+ 8 Li and Λ 9 B→π −+ 9 C ∗→π −+ p+ 8 B decay modes were investigated. The existence of an isospin- 3 2 state of 9Be, with excitation energy 18.6 ± 0.1 MeV and width Γ ≲ 300 keV has been established. From a reanalysis of European K − Collaboration emulsion data, new values of the binding energies of 9 ΛLi and 9 ΛB hypernuclei were found as 8.50 ± 0.12 MeV and 8.29 ± 0.18 MeV, respectively.