相关论文: Hypernuclear potentials and the pseudoscalar meson…
We present a nonrelativistic transition potential for the weak strangeness-changing reaction $\Lambda N \to NN$. The potential is based on a one meson exchange model (OME), where, in addition to the long-ranged pion, the exchange of the…
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…
The evolution of single-particle energies with varying isospin asymmetry in the shell model is an important issue when predicting changes in the shell structure for exotic nuclei. In many cases pseudospin partner levels, that are almost…
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…
By describing strong interactions between hadrons via a relativistic supermultiplet scheme and regarding weak interactions as a perturbation thereof, we derive expressions for nonleptonic weak decay amplitudes in terms of constituent quark…
The existence of isospin admixtures in the physical $\Lambda$, $\pi^o$ complicates the extraction of Delta I=3/2 non-leptonic hyperon decay amplitudes from experimental data, allowing contributions associated with large Delta I=1/2…
The $|\Delta I|=1/2$ rule in non-leptonic decays of hyperons can be naturally understood by postulating a priori mixed physical hadrons, along with the isospin invariance of the responsible transition operator. It is shown that this…
The strangeness-changing ($\Delta S = 1$) weak baryon-baryon interaction is studied through the nonmesonic weak decay of double-$\Lambda$ hypernuclei. Besides the usual nucleon-induced decay $\Lambda N \to N N$ we discuss novel…
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…
Hyperon-nucleon interactions are presented that are derived either in the conventional meson-exchange picture or within leading order chiral effective field theory. The chiral potential consists of one-pseudoscalar-meson exchanges and…
A recently introduced relativistic nuclear energy density functional, constrained by features of low-energy QCD, is extended to describe the structure of hypernuclei. The density-dependent mean field and the spin-orbit potential of a…
Pion-meson-exchange nucleon-nucleon potentials are derived for two nucleons in the intermediate states. The mesons we include are (i) pseudoscalar mesons: $\pi, \eta, \eta'$; (ii) vector mesons: $\rho, \omega, \phi$; (iii) scalar mesons:…
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.
Relativistic mean-field theory with $\delta$ meson, nonlinear isoscalar self-interactions and isoscalar-isovector cross interaction terms with parametrizations obtained to reproduce Dirac-Brueckner-Hartree-Fock calculations for nuclear…
The non-leptonic hyperon decays are analyzed up to one-loop order including all counterterms in the framework of heavy baryon chiral perturbation theory. We use the exchange of the spin-3/2 decuplet resonances as an indication of which…
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…
Nonmesonic weak decays of the A=4, and 5 hypernuclei are studied. The short range parts of the hyperon-nucleon weak interactions are described by the direct quark (DQ) weak transition potential, while the longer range interactions are given…
The experimental observation of lepton-number violating processes would unambiguously indicate the Majorana nature of neutrinos. Various $\Delta L$ = 2 processes for pseudoscalar meson $M_1$ decays to another pseudoscalar meson $M_2$ and…
We analyze the influence of $\sigma$ meson exchange on the main nonmesonic hypernuclear weak decay observables: the total rate, $\Gamma_{NM}$, the neutron-to-proton branching ratio, $\Gamma_{n/p}$, and the proton asymmetry parameter,…
The nonmesonic weak decay spectra of light hypernuclei have been evaluated in a systematic way. As theoretical framework we adopt the independent particle shell model with three different one-meson-exchange transition potentials. Good…