ﻻ يوجد ملخص باللغة العربية
We demonstrate the calculation of the coupling constants and form factors required by effective hadron lagrangians using the quark model. These relations follow from equating expressions for strong transition amplitudes in the two approaches. As examples we derive the NNm nucleon-meson coupling constants and form factors for m = pi, eta, eta, sigma, a_0, omega and rho, using harmonic oscillator quark model meson and baryon wavefunctions and the 3P0 decay model; this is a first step towards deriving a quark-based model of the NN force at all separations. This technique should be useful in the application of effective lagrangians to processes in which the lack of data precludes the direct determination of coupling constants and form factors from experiment.
Short-range quark-quark correlations are introduced into the quark-meson coupling (QMC) model phenomenologically. We study the effect of the correlations on the structure of the nucleon in dense nuclear matter. With the addition of correlations, the
In this paper the dependence of meson-nucleon-nucleon vertex form factors is studied as a function of termperature. The results are obtained starting from a zero temperature Bonn potential. The temperature dependence of the vertex form factors and ra
The spatial distribution of charge and magnetization within the nucleon (proton and neutron) is encoded in the elastic electromagnetic form factors $G_E^{(p,n)}$ and $G_M^{(p,n)}$. These form factors have been precisely measured utilizing elastic ele
We discuss electromagnetic currents in the point-form formulation of relativistic quantum mechanics. The construction is along a spectator model and implies that only one quark is explicitly coupled to the photon, but nevertheless many-body contribut
We use the Nambu-Jona-Lasinio model as an effective quark theory to investigate the medium modifications of the nucleon electromagnetic form factors. By using the equation of state of nuclear matter derived in this model, we discuss the results based