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Factorization Contributions and the Breaking of the $ΔI=1/2$ Rule in Weak $ΛNρ$ and $ΣNρ$ Couplings

Kim Maltman·Mikhail Shmatikov
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Abstract

We compute the modified factorization contributions to the $Λ\rightarrow Nρ$ and $Σ\rightarrow Nρ$ couplings and demonstrate that these contributions naturally include $ΔI=3/2$ terms which are comparable ($\simeq 0.4$ to $-0.8$ times) in magnitude to the corresponding $ΔI=1/2$ terms. As a consequence, we conclude that models which treat vector meson exchange contributions to the weak conversion process $ΛN\rightarrow NN$ assuming such weak couplings to satisfy the $ΔI=1/2$ rule are unlikely to be reliable.

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Kim Maltman, Mikhail Shmatikov. 1995-04-07. Factorization Contributions and the Breaking of the $ΔI=1/2$ Rule in Weak $ΛNρ$ and $ΣNρ$ Couplings. https://doi.org/10.1103/physrevc.51.1576

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