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 $\Delta s=1$ 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.

uuencoded latex file with figures, 14 pages. A factor of two in the numerical values given for the p-wave amplitudes is corrected

References in corpus (2)

• Chiral Perturbation Theory Analysis of the Baryon Magnetic Moments
• Strong and Electromagnetic Decays of the Baryon Decuplet

Cited by in corpus (8)

• The Weak Decay of Hypernuclei
• Meson exchange in the weak decay of Lambda hypernuclei and the Gamma_n/Gamma_p ratio
• Hyperons in Two Flavor Chiral Perturbation Theory
• Novel Weak Decays in Doubly Strange Systems
• Role of deformation in the nonmesonic decay of light hypernuclei
• The Weak $\Lambda \Lambda K^0$ Interaction
• Decay of Hypernuclei
• $NNK$ and $\Lambda \Lambda K$ Amplitudes in Chiral Perturbation Theory