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arXiv · hep-ph/9508287

Kaon-Nucleon Couplings for Weak Decays of Hypernuclei

Abstract

We investigate the weak kaon-nucleon (NNK) S-wave and P-wave interactions using heavy baryon chiral perturbation theory. The leading 1-loop SU(3) breaking contributions to the $ppK$, $pnK$, and $nnK$ couplings are computed. We find that they suppress all NNK amplitudes by $30\%$ to $50\%$. The ratio of neutron-induced to proton-induced hypernuclear decay widths is sensitive to such reductions. It has been argued that the discrepancy between the predicted and observed P-wave amplitudes in $Δs=1$ hyperon decay results from an accidental cancellation between tree-level amplitudes, and is not a fundamental problem for chiral perturbation theory. Agreement between experimentally determined NNK P-wave amplitudes and our estimates would support this explanation.

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BibTeXRIS

M. J. Savage, R. P. Springer. 1996-08-02. Kaon-Nucleon Couplings for Weak Decays of Hypernuclei. https://doi.org/10.1103/physrevc.53.441%2010.1103%2Fphysrevc.54.2786

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