Abstract
The FINUDA experiment performed a systematic study of the charged mesonic weak decay channel of p-shell Λ-hypernuclei. Negatively charged pion spectra from mesonic decay were measured with magnetic analysis for the first time for 7ΛLi, 9ΛBe, 11ΛB and 15ΛN. 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+ for 7ΛLi and 5 / 2+ for 11ΛB ground-state are confirmed and a spin-parity 3 / 2+ for 15ΛN ground-state is assigned for the first time.
Original language | English |
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Pages (from-to) | 139-146 |
Number of pages | 8 |
Journal | Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics |
Volume | 681 |
Issue number | 2 |
DOIs | |
State | Published - 26 Oct 2009 |
Keywords
- Ground-state spin assignment
- Mesonic decay
- p-Shell Λ-hypernuclei