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Nonmesonic weak decay of light hypernuclei with coherent $Sigma$ mixing

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 نشر من قبل Kenji Sasaki
 تاريخ النشر 2002
  مجال البحث
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Nonmesonic weak decays of the A=4, and 5 hypernuclei are studied. The short range parts of the hyperon-nucleon weak interactions are described by the direct quark (DQ) weak transition potential, while the longer range interactions are given by the $pi$ and $K$ meson exchange processes. Virtual $Sigma$ mixings of the coherent type are found to give significant effects on the decay rates of $^4_{Lambda}{rm He}$. A large violation of the $Delta I = 1/2$ rule is predicted in the J=0 transition amplitudes.



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