The Schwinger-Dyson equations for the nucleon and meson propagators are solved self-consistently in an approximation that goes beyond the Hartree-Fock approximation. The traditional approach consists in solving the nucleon Schwinger-Dyson equation with bare meson propagators and bare meson-nucleon vertices; the corrections to the meson propagators are calculated using the bare nucleon propagato...

Investigations of the spin composition of the nucleon have led to surprising insights, beginning with the revelation that the majority of its spin is carried by quark and gluonic orbital angular momenta and gluon spin rather than by quark helicity. In addition, considerable effort has gone into understanding, predicting and measuring the transversity distribution, h1(x), of the nucleon. 3 Trans...

The pion exchange between nucleons generates a strong tensor interaction, which provides large attractive contribution for the binding energy of nucleus. This non-central tensor interaction is difficult to handle in the shell model framework, which hinders full understanding of nuclear structure. We develop the tensor optimized shell model (TOSM) for the strong tensor interaction and now we are...

A review is presented of the development and current status of nuclear shell-model calculations in which the two-body effective interaction between the valence nucleons is derived from the free nucleon-nucleon potential. The significant progress made in this field within the last decade is emphasized, in particular as regards the so-called Vlow−k approach to the renormalization of the bare nucl...

We present a model calculation of the generalized parton distributions where the nucleon is described by a quark core surrounded by a mesonic cloud. In the one-meson approximation, we expand the Fock state of the physical nucleon in a series involving a bare nucleon and two-particle, meson-baryon, states. We discuss the role of the different Fock-state components of the nucleon by deriving a co...

A model calculation of nucleon-nucleon scattering is presented, which results in an amplitude that in the elastic high energy limit realizes the Wu-Yang idea regarding the relation between the elastic form factor of the nucleon and the differential cross section; and which is consistent with the behavior of the differential cross section for the production of nucleon resonances. The calculation...

The behavior of the nuclear matter response in the region of large momentum transfer, in which plane wave impulse approximation predicts the onset of y-scaling, is discussed. The theoretical analysis shows that scaling violations produced by final state interactions are driven by the momentum dependence of the nucleon-nucleon scattering cross section. Their study may provide valuable informatio...

I discuss developments in the area of nucleon resonance excitation, aimed at putting our understanding of nucleon structure in the regime of strong QCD on a qualitatively new level. They involve the collection of high quality data in various channels, a more rigorous approach in the search for “missing” resonances, an effort to compute some critical quantities in nucleon resonance excitations f...

Vector meson photoproduction and electroproduction have been suggested as a tool to find or confirm the nucleon resonances. In order to extract more reliable informations on the nucleon resonances, understanding the non-resonant background is indispensable. We consider final state interactions in ω photoproduction as a background production mechanism. For the intermediate states, we consider nu...

We perform ab initio calculations for nuclei around 16O, 40Ca, and 56Ni using realistic nucleon-nucleon forces. In particular, 56Ni is computed as the heaviest nucleus in this kind of ab initio calculation. Ground-state and single-particle energies including three-body-cluster effects are obtained within the framework of the unitary-model-operator approach. It is shown that the CD-Bonn nucleon-...