Neutron and proton energy spectra from the non - mesonic weak decays of 5 Λ He and 12 Λ C
نویسندگان
چکیده
We have simultaneously measured the energy spectra of neutrons and protons emitted in the non-mesonic weak decays of 5 Λ He and 12 Λ C hypernuclei produced via the (π,K) reaction with much higher statistics over those of previous experiments. The neutron-to-proton yield ratios for both hypernuclei at a high energy threshold (60 MeV) were approximately equal to two, which suggests that the ratio of the neutronand proton-induced decay channels, Γn(Λn → nn)/Γp(Λp → np), is about 0.5. In the neutron energy spectra, we found that the yield of the low-energy component is unexpectedly large, even for 5 Λ He.
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