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Related papers: Nonmesonic Weak Decay Spectra and Three-Nucleon Em…

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We have simultaneously measured the energy spectra of neutrons and protons emitted in the non-mesonic weak decays of 5_Lambda-He and 12_Lambda-C hypernuclei produced via the (pi^+,k^+) reaction with much higher statistics over those of…

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…

Nuclear Theory · Physics 2007-05-23 W. M. Alberico , G. Garbarino , A. Parreno , A. Ramos

Theoretical descriptions of the non-mesonic weak decay of Lambda-hypernuclei are unable to reproduce the experimental values of the ratio Gn/Gp=G(Lambda n -> nn)/G(Lambda p -> np). In this contribution we discuss a new approach to this…

Nuclear Theory · Physics 2009-11-10 G. Garbarino , A. Parreno , A. Ramos

The decay of $\Lambda$-hypernuclei without pion emission, known as Non Mesonic Weak Decay (NMWD), gives an effective tool to investigate $\Delta$S=1 four-baryon interactions. It was theoretically suggested that the two-nucleon induced…

The FINUDA experiment performed a systematic study of the charged mesonic weak decay channel of $p$-shell $\Lambda$-hypernuclei. Negatively charged pion spectra from mesonic decay were measured with magnetic analysis for the first time for…

We derive general explicit expressions for a shell-model calculation of the intrinsic asymmetry parameter, $a_\Lambda$, in nonmesonic weak hypernuclear decay. They include the effects of three-body kinematics in the final states of the…

Nuclear Theory · Physics 2016-09-08 Cesar Barbero , Alfredo P. Galeao , Francisco Krmpotic

The ratio N_{nn}/N_{np} between the number of neutron-neutron and neutron--proton pairs emitted in the non--mesonic weak decay of \Lambda-hypernuclei is calculated within a nuclear matter formalism extended to ^{12}_{Lambda}C via the local…

Nuclear Theory · Physics 2015-05-18 E. Bauer , G. Garbarino

The weak nonmesonic decay of Lambda-hypernuclei is studied in the context of a one-meson-exchange model. Predictions are made for the decay rate, p/n stimulation ratio and the asymmetry in polarized hypernuclear decay.

Nuclear Theory · Physics 2008-11-26 John F. Dubach , Geoffrey B. Feldman , Barry R. Holstein , Lorenzo de la Torre

Decays of $\Lambda$ in nuclei, nonmesonic mode, are studied by using the $\Lambda N \to NN$ weak transition potential derived from the meson exchange mechanism and the direct quark mechanism. The decay rates are calculated both for the…

Nuclear Theory · Physics 2009-10-31 K. Sasaki , T. Inoue , M. Oka

Previous studies of proton and neutron spectra from Non-Mesonic Weak Decay of eight Lambda-Hypernuclei (A = 5-16) have been revisited. New values of the ratio of the two-nucleon and the one-proton induced decay widths, Gamma_2N/Gamma_p, are…

The main open problem in the physics of Lambda-hypernuclei is the lack of a sound theoretical interpretation of the large experimental values for the ratio G_n/G_p. To approach the problem, we have incorporated a Lambda N-> nN…

Nuclear Theory · Physics 2008-11-26 G. Garbarino , A. Parreno , A. Ramos

Having in mind its future extension for theoretical investigations related to charmed nuclei, we develop a relativistic formalism for the nonmesonic weak decay of single-$\Lambda$ hypernuclei in the framework of the independent-particle…

Nuclear Theory · Physics 2016-04-20 C. E. Fontoura , F. Krmpotić , A. P. Galeão , C. De Conti , G. Krein

A general shell model formalism for the nonmesonic weak decay of the hypernuclei has been developed.It involves a partial wave expansion of the emitted nucleon waves,preserves naturally the antisymmetrization between the escaping particles…

Nuclear Theory · Physics 2007-05-23 F. Krmpotic , D. Tadic

We have obtained the decay asymmetry parameters in non-mesonic weak decay of polarized Lambda-hypernuclei by measuring the proton asymmetry. The polarized Lambda-hypernuclei, 5_Lambda-He, 12_Lambda-C, and 11_Lambda-B, were produced in high…

The nonmesonic weak decay of $\Lambda$ hypernuclei using nonrelativistic nuclear matter is studied. As the basic building block we use the Polarization Propagator Method developed by Oset and Salcedo. It is shown that the exact calculation…

Nuclear Theory · Physics 2016-09-08 E. Bauer , F. Krmpotic

Recent progress has been experienced in the field of hypernuclear weak decay, especially concerning the ratio of the neutron- to proton-induced Lambda non-mesonic decay rates, G_n/G_p. Theoretical analyses of nucleon coincidence data have…

Nuclear Theory · Physics 2011-01-20 E. Bauer , G. Garbarino , A. Parreno , A. Ramos

A fully relativistic finite nucleus wave-function approach to the non-mesonic weak decay of the ${_\Lambda^{12} C}$ hypernucleus is presented. The model is based on the calculation of the amplitudes of the tree-level Feynman diagrams for…

Nuclear Theory · Physics 2015-03-13 Francesco Conti , Andrea Meucci , Carlotta Giusti. Franco Davide Pacati

We compute one- and two-nucleon kinetic-energy spectra and opening-angle distributions for the nonmesonic weak decay of several hypernuclei, and compare our results with some recent data. The decaymics is described by transition potentials…

Nuclear Theory · Physics 2014-11-20 Eduardo Bauer , Alfredo P. Galeao , Mahir S. Hussein , Francisco Krmpotic

We have measured the energy spectra of pions and protons emitted in the weak decay of 12_Lambda_C, 28_Lambda_Si, and Lambda_Fe hypernuclei produced via the (pi+, K+) reaction. The decay widths of the pi- mesonic decay (Lambda -> p + pi-)…

The non-mesonic weak decay of polarized Lambda-hypernuclei is studied for the first time by taking into account, with a Monte Carlo intranuclear cascade code, the nucleon final state interactions. A one-meson-exchange model is employed to…

Nuclear Theory · Physics 2016-09-08 W. M. Alberico , G. Garbarino , A. Parreno , A. Ramos