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Towards a solution of the Gn/Gp puzzle in the weak decay of Lambda-hypernuclei

W. M. Alberico·G. Garbarino·A. Parreno·A. Ramos
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Abstract

In this contribution we discuss an evaluation of double-nucleon coincidence spectra for the non-mesonic weak decay of Lambda-hypernuclei. The results have been obtained by combining a one-meson-exchange model for the Lambda N -> nN transition in finite nuclei with a Monte Carlo code accounting for the nucleon final state interactions. A weak-decay-model independent analysis of KEK coincidence data allows us to extract Gn/Gp values around 0.3-0.4 for 5_Lambda-He and 12_Lambda-C, thus representing an important progress towards the solution of the Gn/Gp puzzle. Preliminary results for the angular asymmetries in the non-mesonic weak decay of polarized hypernuclei are also presented.

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W. M. Alberico, G. Garbarino, A. Parreno, A. Ramos. 2004-07-16. Towards a solution of the Gn/Gp puzzle in the weak decay of Lambda-hypernuclei. https://arxiv.org/abs/nucl-th/0407046

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