Related papers: Relationships between nonmesonic-weak-decays in di…
Using the recent measurement of the $\Xi ^0 \to \Lambda \gamma $ asymmetry as an input, we reanalyse nonleptonic and weak radiative hyperon decays in a single symmetry-based framework. In this framework the old S:P problem of nonleptonic…
We establish the bridge between the commonly used Nabetani-Ogaito-Sato-Kishimoto (NOSK) formula for the asymmetry parameter $a_\Lambda$ in the $\vec\Lambda p \to np$ emission of polarized hypernuclei, and the shell model (SM) formalism for…
We use the self-consistent mean-field theory to discuss the ground state and decay properties of $\Lambda$ hypernuclei. We first discuss the deformation of $\Lambda$ hypernuclei using the relativistic mean-field (RMF) approach. We show…
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…
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…
We take an approach to the $\Lambda$ nonmesonic weak decay in nuclei based on the exchange of mesons under the guidelines of chiral Lagrangians. The one pion and one kaon exchange are considered, together with the exchange of two pions,…
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…
Based on realistic calculations for the nonmesonic decay rate of Hypertriton we demonstrate, that in principle it is not possible to measure the total n- and p- induced decay rates and as a consequence $\Gamma_n /\Gamma_p$ for that lightest…
Two different approaches have been employed for the evaluation of the decay widths of Lambda-hypernuclei (ranging from $^5_{\Lambda}$He to $^{208}_{\Lambda}$Pb) with the polarization propagator method. In ref.[1], the two-nucleon stimulated…
We update our previous results for the nonmesonic decay of $^{12}_\Lambda$C and $^5_\Lambda$He. We pay special attention to the role played by Final State Intreractions on the decay observables. We follow a One-Meson-Exchange model which…
We study nonleptonic Lambda_b -> Lambda_c pi, Sigma_c pi and Sigma_c^* pi decays in the limit m_b, m_c, E_pi >> Lambda_{QCD} using the soft-collinear effective theory. Here Sigma_c = Sigma_c(2455) and Sigma_c^* = Sigma_c(2520). At leading…
The contribution of Pauli exchange terms to the two--nucleon induced non--mesonic weak decay of $^{12}_\Lambda$C hypernuclei, $\Lambda NN\to nNN$ ($N=n$ or $p$), is studied within a nuclear matter formalism implemented in a local density…
We first determine the Lambda-N S-wave phase shifts so as to reproduce the experimental Lambda separation energies of A=3, 4 Lambda-hypernuclei, and then construct three phase-equivalent Lambda-N potentials with different central repulsion.…
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…
The weak production of Lambdas in nucleon-nucleon scattering is studied in a meson-exchange framework. The weak transition operator for the $NN \to N \Lambda$ reaction is identical to a previously developed weak strangeness-changing…
We review the mechanism of weak decay of hypernuclei, with emphasis on the non-mesonic decay channels. Various theoretical approaches are discussed and the results are compared with the available experimental data.
Violations of the $\Delta$I=1/2 rule are investigated in the nonmesonic weak hypernuclear decay using a weak $\Lambda$N$\to$NN transition potential based on meson exchange. While the weak $\Delta$I=3/2 matrix elements of baryons with…
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 $\Lambda N\rightarrow NN$,…
We present new calculations of the leading-order one-loop amplitude and the decay rate for $H\to \nu \bar{\nu} \gamma$ within the standard model, employing reduction to a set of basic Passarino-Veltman functions resulting in more concise…
To comprehend the recent Brookhaven National Laboratory experiment E788 on $^4_\Lambda$He, we have outlined a simple theoretical framework, based on the independent-particle shell model, for the one-nucleon-induced nonmesonic weak decay…