Search for heavy lithium isotopes 10-12Li in stopped pion absorption reactions

Abstract

The experimental search for the production of heavy lithium isotopes 10-12Li was carried out in the stopped π−-mesons absorption reactions on the targets 11B, 12,14C. Study of 10Li was performed in the correlation and inclusive measurements of reactions 12C(π−,pp)X, 14C(π−,pt)X, 14C(π−,dd)X and 11B(π−,p)X. Three highly excited states of 10Li with the resonance energies Er = 6.1 ± 0.1 MeV, 7.8 ± 0.1 MeV and 10.1 ± 0.1 MeV were identified together with the well-known levels. The resonance parameters of three low-lying excited states of 11Li were determined in the 14C(π−,pd)X reaction. In the 14C(π−,pp)X reaction 12Li excited state with Er = 4.0 ± 0.2 MeV and an indication on a level with Er ≈ 7 MeV were found.