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Related papers: Weak Decay of Lambda Hypernuclei

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We have determined the spectra of neutrons and protons following the decay of $\Lambda$ hypernuclei through the one- and two-nucleon induced mechanisms. The momentum distributions of the primary nucleons are calculated and a Monte Carlo…

Nuclear Theory · Physics 2014-11-18 A. Ramos , M. J. Vicente-Vacas , E. Oset

One of the main open problems in the physics of Lambda-hypernuclei is the lack of a sound theoretical interpretation of the large experimental values for the ratio Gn/Gp=G(Lambda n -> nn)/G(Lambda p -> np). To approach the problem, we have…

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

A consistent microscopic diagrammatic approach is applied for the first time to the calculation of the nucleon emission spectra in the non-mesonic weak decay of Lambda-hypernuclei. We adopt a nuclear matter formalism extended to finite…

Nuclear Theory · Physics 2015-03-19 E. Bauer , G. Garbarino

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

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-)…

We analyze the recent data on the non-mesonic decays of light Lambda-hypernuclei up to ^12_Lambda C using the phenomenological model of Block and Dalitz. Fitting the spin-isospin dependent Lambda N -> NN reaction rates to six data points,…

Nuclear Theory · Physics 2008-11-26 Namyoung Lee , Hong Jung , Dongwoo Cha

We calculate the $\Lambda \Lambda \to YN$ transition rate of ${^{\phantom{\Lambda}6}_{\Lambda \Lambda}}$He by the hybrid picture, the $\pi$ and $K$ exchanges plus the direct quark processes. It is found that the hyperon-induced decay is…

Nuclear Theory · Physics 2010-04-05 K. Sasaki , T. Inoue , M. Oka

A few aspects of the $\Lambda$ mesonic and non-mesonic decay in nuclei are shortly addressed.

Nuclear Theory · Physics 2009-09-25 W. M. Alberico , M. B. Barbaro , A. Molinari

The non-mesonic weak decay of $\Lambda$-hypernuclei is studied within a microscopic diagrammatic approach which includes, for the first time, the effect or the $\Delta$-baryon resonance. We adopt a nuclear matter formalism extended to…

Nuclear Theory · Physics 2015-06-05 E. Bauer , G. Garbarino

The nonmesonic decay of $\Lambda$-hypernuclei provides access to the nonleptonic weak decay process $\Lambda N \to NN$, which is achievable only through the observation of hypernuclear ground-state decays. We continue the discussion of some…

Nuclear Theory · Physics 2010-12-06 L. Majling , O. Majlingova

Because of Pauli suppression effects the $N\pi$ decay of the free $\Lambda$ is not of importance in hypernuclei with $A\geq 10$. Rather the decay of such hypernuclei proceeds via the nucleon-stimulated mode $\Lambda N\rightarrow NN$,…

Nuclear Theory · Physics 2007-05-23 Barry R. Holstein

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…

A direct experimental evidence of the occurrence of the weak reaction $\Lambda np\rightarrow nnp$ in nuclei has been obtained by the FINUDA experiment. Three events have been found that can be attributed to $^{7}_{\Lambda}$Li and…

The nonmesonic weak decay of $\Lambda$ hypernuclei is studied in a shell model framework. A complete strangeness-changing weak $\Lambda N \to NN$ transition potential, based on one boson exchange, is constructed by including the exchange of…

Nuclear Theory · Physics 2008-11-26 A. Parreño , A. Ramos , C. Bennhold

The Lambda decay rates in nuclei has been calculated in ref. 1 using the Propagator Method in Local Density Approximation. We have studied the dependence of the widths (including the one for the two-body induced process Lambda NN -> NNN) on…

Nuclear Theory · Physics 2017-08-23 W. M. Alberico , A De Pace , G. Garbarino , A. Ramos

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

Nonmesonic weak decays of s-shell hypernuclei are analyzed in microscopic models for the Lambda N to NN weak interaction. A scalar-isoscalar meson, sigma, is introduced and its importance in accounting the decay rates, n/p ratios and proton…

Nuclear Theory · Physics 2009-11-10 K. Sasaki , M. Izaki , M. Oka

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

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…

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