Related papers: Comment on "Mass and K Lambda coupling of N*(1535)…
We study Little Higgs models based on a SU(3)_1 x SU(3)_2 global symmetry and with two scales (the two vacuum expectation values f_{1,2}) substantially different. We show that all the extra vector boson fields present in these models may be…
We investigate the structure of the Lambda(1405) resonance and Kbar N phenomenology in the perspective of chiral SU(3) dynamics. Utilizing the chiral coupled-channel approach which well describes the Kbar N scattering observable, we perform…
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…
Poincare' covariant Faddeev equations for the nucleon and Delta are solved to illustrate that an internally consistent description in terms of confined-quark and nonpointlike confined-diquark-correlations can be obtained. pi N-loop induced…
The $S$-wave $\Lambda K$ and $\Sigma K$ states with isospin $I=1/2$ are dynamically investigated within the framework of the chiral SU(3) quark model by solving a resonating group method (RGM) equation. The model parameters are taken from…
A K \bar{K} N system with I=1/2 and J^P=1/2^+ is investigated with non-relativistic three-body calculations by using effective \bar K N, K \bar K and KN interactions. The \bar K N interaction describes the Lambda(1405) as a \bar K N…
We suggest an approach to explain the observed pattern of the neutrino masses and mixing which employs the weakly broken quark-lepton symmetry and does not require introduction of an ad hoc symmetry of the neutrino sector. The mass matrices…
The coupled pi+N, eta+N, gamma+N systems are described by a K-matrix method. The parameters in this model are adjusted to get an optimal fit to pi+N -> pi+N, pi+N -> eta+N, gamma+N -> pi+N and gamma+N -> eta+N data in an energy range of…
Differential cross sections and photon-beam asymmetries for the gamma p -> K+ Lambda(1520) reaction have been measured with linearly polarized photon beams at energies from the threshold to 2.4 GeV at 0.6<cos(theta)<1. A new bump structure…
The mass matrices of quarks have a simple structure if expressed in powers of the small parameter \sigma=(m_c/m_t)^{1/2}. If there is a close relation between quarks and leptons, one would expect similar structures for the lepton matrices…
We derive closed form kaon-nucleon scattering amplitudes using the ``quark Born diagram" formalism, which describes the scattering as a single interaction (here the OGE spin-spin term) followed by quark line rearrangement. The low energy…
A detailed phenomenological analysis of neutral kaon mixing in "little Randall-Sundrum" models is presented. It is shown that the constraints arising from the CP-violating quantity epsilon_K can, depending on the value of the ultra-violet…
We investigate the weak kaon-nucleon (NNK) S-wave and P-wave interactions using heavy baryon chiral perturbation theory. The leading 1-loop SU(3) breaking contributions to the $ppK$, $pnK$, and $nnK$ couplings are computed. We find that…
We investigate the p(gamma,K+)Lambda and p(gamma,K+)Sigma^0 reactions within a coupled-channels effective-Lagrangian method which is based on the K-matrix approach. The two-body final channels included are pi-N, eta-N, phi-N, rho-N,…
Recently there has been considerable interest in the subject of molecules, which are weakly bound states of hadron pairs. The question of the existence of molecules is closely related to the more general problem of the determination of low…
We study the photoproduction of $K^*(892)$ vector meson from both the charged and neutral reactions, $\gamma p \to K^{*+} \Lambda$ and $\gamma n \to K^{*0} \Lambda$. The production mechanisms that we consider include $t$-channel $K^*$, $K$,…
A recently developed quark model approach to pseudoscalar meson photoproduction is extended to electroproduction process for the $\eta$ meson in the kinematics of momentum transfer $Q^2 \leq$ 4 (GeV/c)$^2$ and total center of mass energy $W…
We report our recent effort for the extraction of resonance parameters (complex pole mass and residues etc.) associated with Lambda* and Sigma* hyperons. This was accomplished via a comprehensive partial-wave analysis of the data for K^- p…
The \Lambda_c(2940)^+ baryon is studied in a constituent quark model as a molecular state composed by nucleons and D^* mesons. A bound state with the right binding energy is found for the J^\pi=3/2^- channel. The partial widths…
Neutron spectra from the reaction $K^-+d\rightarrow \pi+\Sigma+n$ were calculated in the energy range $E^{cm}_{K^-}= 0-50\ MeV$ using coupled channel Faddeev equations for the description of the $\bar KNN-\pi\Sigma N$ three-body system. The…