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Exploring Hyperons and Hypernuclei with Lattice QCD

S. R. Beane·P. F. Bedaque·A. Parreno·M. J. Savage
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Abstract

In this work we outline a program for lattice QCD that would provide a first step toward understanding the strong and weak interactions of strange baryons. The study of hypernuclear physics has provided a significant amount of information regarding the structure and weak decays of light nuclei containing one or two Lambda's, and Sigma's. From a theoretical standpoint, little is known about the hyperon-nucleon interaction, which is required input for systematic calculations of hypernuclear structure. Furthermore, the long-standing discrepancies in the P-wave amplitudes for nonleptonic hyperon decays remain to be understood, and their resolution is central to a better understanding of the weak decays of hypernuclei. We present a framework that utilizes Luscher's finite-volume techniques in lattice QCD to extract the scattering length and effective range for Lambda-N scattering in both QCD and partially-quenched QCD. The effective theory describing the nonleptonic decays of hyperons using isospin symmetry alone, appropriate for lattice calculations, is constructed.

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S. R. Beane, P. F. Bedaque, A. Parreno, M. J. Savage. 2003-11-07. Exploring Hyperons and Hypernuclei with Lattice QCD. https://doi.org/10.1016/j.nuclphysa.2004.09.081

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