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تسجيل مستخدم جديدWeak Decay of $Lambda$ in Nuclei : Quarks vs Mesons
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Decays of $Lambda$ in nuclei, nonmesonic mode, are studied by using the $Lambda N to NN$ weak transition potential derived from the meson exchange mechanism and the direct quark mechanism. The decay rates are calculated both for the $Lambda$ in symmetric nuclear matter and light hypernuclei. We consider the exchange of six mesons ($pi, K, eta, rho, omega, K^ast$). The form factor in the meson exchange mechanism and short range correlation are carefully studied.
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The non-mesonic weak decay of polarized Lambda-hypernuclei is studied for the first time by taking into account, with a Monte Carlo intranuclear cascade code, the nucleon final state interactions. A one-meson-exchange model is employed to describe th
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