Missing mass spectroscopy with the (e,e′K+) reaction was performed at Jefferson Laboratory's Hall C for the neutron-rich Λ hypernucleus LiΛ9. The ground-state (g.s.) energy was obtained to be BΛg.s.=8.84±0.17stat.±0.15sys.MeV by using shell-model calculations of a cross-section ratio and an energy separation of the spin doublet states (3/21+ and 5/21+). In addition, peaks that are considered to be states of [Li8(3+) - sΛ=3/22+,1/2+] and [Li8(1+) - sΛ=5/22+,7/2+] were observed at EΛ(no.2)=1.74±0.27stat.±0.11sys. and EΛ(no.3)=3.30±0.24stat.±0.11sys.MeV, respectively. The EΛ(no.3) is larger than shell-model predictions by a few hundred keV, and the difference would indicate that a He5+t structure is more developed for the 3+ state than those for the 2+ and 1+ states in a core nucleus Li8 as a cluster model calculation suggests.
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