New results on Mesonic Weak Decay of $p$-shell $Lambda$-Hypernucle

The FINUDA experiment performed a systematic study of the charged mesonic weak decay channel of 7Λ Li and 5/2+ for 11 ΛB ground-state are confirmed and a spin-parity 3/2+ for 15 ΛN ground-state is assigned for the first time. p-shell Λ-hypernuclei. Negatively charged pion spectra from mesonic decay were measured with magnetic analysis for the first time for 7Λ Li, 9 ΛBe, 11 ΛB and 15 ΛN. The shape of the π− spectra was interpreted through a comparison with pion distorted wave calculations that take into account the structure of both hypernucleus and daughter nucleus. Branching ratios Γπ−/Γtot were derived from the measured spectra and converted to π− decay rates Γπ− by means of known or extrapolated total decay widths Γtot of p-shell Λ-hypernuclei. Based on these measurements, the spin-parity assignment 1/2+ fo