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$π^+$ Emission from Hypernuclei and the Weak $ΔI=3/2$ Transitions

Makoto Oka
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Abstract

Low energy $π^+$ emission in hypernuclear weak decays is studied in the soft pion limit. It is found that the $π^+$ decay amplitude is dominated by the $ΔI=3/2$ part of nonmesonic weak decays according to the soft pion theorem. The ratios, $R(π^+/soft π^-) $, for light hypernuclei are estimated in the direct quark mechanism, which predicts violation of the $ΔI=1/2$ rule, and found to be about 1/3 for $^4_ΛHe$.

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Makoto Oka. 1999-01-05. $π^+$ Emission from Hypernuclei and the Weak $ΔI=3/2$ Transitions. https://doi.org/10.1016/s0375-9474(99)00007-x

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