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Direct Quark Mechanism for Weak $\Lam N \leftrightarrow NN$ Processes

Makoto Oka
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Abstract

Two body weak processes $ΛN \leftrightarrow NN$ are studied from the viewpoint of quark substructure of baryons.They can be studied in nonmesonic weak decays of hypernuclei and also hyperon production in the $NN$ scattering. The direct quark mechanism in contrast to the one-pion exchange mechanism is shown to give sizable $\di=3/2$ contribution in the J=0 channel. Nonmesonic decay rates of $^4_Λ$H, $^4_Λ$He, and $^5_Λ$He agree with the current experimental data fairly well. Especially the $n/p$ ratio is enhanced by the direct quark contribution. The cross sections for $pn\to \Lam p$ scattering are studied in the quark cluster model approach.

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Makoto Oka. 1998-01-16. Direct Quark Mechanism for Weak $\Lam N \leftrightarrow NN$ Processes. https://doi.org/10.1016/s0375-9474(98)00289-9

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