Meson exchange in the weak decay of /Λ hypernuclei and the Γn/Γp ratio
Abstract
We take an approach to the Λ nonmesonic weak decay in nuclei based on the exchange of mesons. The one-pion and one-kaon exchange are considered, together with the exchange of two pions, either correlated, leading to an important scalar-isoscalar exchange ( σ-like exchange), or uncorrelated (box diagrams). Extra effects of ω exchange in the scalar-isoscalar channel are also considered. Constraints of chiral dynamics are used to generate these exchanges. A drastic reduction of the OPE results for the Γn/ Γp ratio is obtained and the new results are compatible with all present experiments within errors. The absolute rates obtained for different nuclei are also in good agreement with experiment.
- Publication:
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Nuclear Physics A
- Pub Date:
- November 2001
- DOI:
- 10.1016/S0375-9474(01)01085-5
- arXiv:
- arXiv:nucl-th/0101051
- Bibcode:
- 2001NuPhA.694..525J
- Keywords:
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- Nuclear Theory
- E-Print:
- 30 pages, 16 figures, 8 tables, to be published in Nucl. Phys. A