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$ΛN \to NN$ weak interaction in effective field theory

Assumpta Parreno·Cornelius Bennhold·Barry R. Holstein
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Abstract

The nonleptonic weak $|ΔS|=1$ $ΛN$ interaction, responsible for the dominant nonmesonic decay of all but the lightest hypernuclei, is studied in the framework of an effective field theory. The long-range physics is described through tree-level exchange of the SU(3) Goldstone bosons, while the short-range potential is parametrized in terms of the lowest-order contact terms. We obtain reasonable fits to available weak hypernuclear decay rates and quote the values for the parity-violating asymmetry as predicted by the present effective field theory.

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Assumpta Parreno, Cornelius Bennhold, Barry R. Holstein. 2004-09-28. $ΛN \to NN$ weak interaction in effective field theory. https://doi.org/10.1103/physrevc.70.051601

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