Related papers: Composite nucleons in scalar and vector mean-field…
Using the quark-meson coupling (QMC) model, we study nuclear matter from the point of view of quark degrees of freedom. Performing a re-definition of the scalar field in matter, we transform QMC to a QHD-type model with a non-linear scalar…
We calculate nucleon-nucleon cross sections in the nuclear medium with unequal densities of protons and neutrons. We use the Dirac-Brueckner-Hartree-Fock approach together with realistic nucleon-nucleon potentials. We examine the effect of…
The nucleons (protons and neutrons) are by far the most abundant form of matter in our visible Universe; they are composite particles made of quarks and gluons, the fundamental quanta of Quantum Chromo Dynamics (QCD). The usual…
A compelling feature of relativistic mean-field phenomenology has been the reproduction of spin-orbit splittings in finite nuclei after fitting only to equilibrium properties of infinite nuclear matter. This successful result occurs when…
The effects of the Dirac sea of the nucleons are investigated within a covariant model of the hadronic interaction. We extend the usual Mean Field Approximation and present a procedure to deal with divergences which are proportional to…
In the covariant quark-diquark model the effective Bethe-Salpeter (BS) equations for the nucleon and the $\Delta$ are solved including scalar {\em and axialvector} diquark correlations. Their quark substructure is effectively taken into…
The effects of internal quark structure of baryons on the composition and structure of neutron star matter with hyperons are investigated in the quark-meson coupling (QMC) model. The QMC model is based on mean-field description of…
In this chapter we give a pedagogical introduction to the constituent quark model. The explanation of magnetic moments of the nucleons was crucial to introduce an effective quark mass for light quarks that nowadays are understood as an…
We present a new perturbative approach to QCD based on the use of quark composites with hadronic quantum numbers as fundamental variables. We apply it to the case of the nucleons by performing a nonlinear change of variables in the Berezin…
The mass of the nucleon is studied in a chiral quark-diquark model. Both scalar and axial-vector diquarks are taken into account for the construction of the nucleon state. After the hadronization procedure to obtain an effective…
The electromagnetic form factors of the nucleon are calculated in an extended chiral constituent-quark model where the effective interaction is described by the exchange of pseudoscalar, vector, and scalar mesons. Two-body current-density…
Interplay between the dependence of symmetry energy on density and the variation of nucleonic densities across nuclear surface is discussed. That interplay gives rise to the mass dependence of the symmetry coefficient in an energy formula.…
A quark-model framework for studying nuclear medium effects on nucleon resonances is described and applied here to pion photoproduction on the deuteron, which is the simplest composite nucleon system and serves as a first test case. Pion…
We discuss the relevance of the scalar modes appearing in chiral theories with spontaneous symmetry breaking such as the NJL model for nuclear matter studies. We show that it depends on the relative role of chiral symmetry breaking and…
The work that Peter Schuck and I carried out during the nineties in collaboration with the Lyon and Darmstadt theory groups is summarized. I retrace how our theoretical developments combined with experimental results concerning the…
We extend the QCD Parton Model analysis by employing a factorized nuclear structure model that explicitly accounts for both individual nucleons and correlated nucleon pairs. This novel framework establishes a paradigm that directly links…
The existence of quark matter inside the cores of heavy neutron stars is a possibility which can be probed with modern astrophysical observations. We use an (axial)vector meson extended quark-meson model to describe quark matter in the core…
A mechanism to have the quark mass hierarchy in the supersymmetric composite model is proposed. The source of the hierarchy is the kinetic-term mixing between composite quarks. Such mixing can be expected, if quarks are composite particles.…
The problem of the structure of nucleons and their interaction in the concept of nonperturbative QCD is discussed as an approach to studying the transformation of current quarks into constituent ones and the search for the mechanism of such…
A nuclear model is proposed where the nucleons interact by emitting and absorbing mesons, and where the mesons are treated explicitly. A nucleus in this model finds itself in a quantum superposition of states with different number of…