The spin dependence of an weak interaction in the decay of hypernuclei

From an analysis of 468 hypernuclei (HFs) with ranges > 120 μ m, the non-mesic to π--mesic ratio (Q-) for ΛHe and ΛHe5 HFs was found to be 1.37 ± 0.17 and 1.58± 0.20 respectively. This data, together with results on ΛHe4 and heavy hypernuclei, has been used to deduce spin dependences for Λn and ΛP weak interactions in decay of hypernuclei. It is found that the rates for triplet and singlet interactions between Λ and neutron are 22 ΓΛ and 11 ΓΛ and for Λ and proton are 8.2 ΓΛ and 5.5 ΓΛ respectively, where ΓΛ is the decay rate of Λ. The total decay rates for ΛHe4 and ΛHe5 are 1.28 ΓΛ and 0.99 ΓΛ and the non-mesic decay rates are 0.17 ΓΛ and 0.51 ΓΛ respectively