ar X iv : n uc l - th / 9 70 50 11 v 1 5 M ay 1 99 7 Effective Q - Q interactions in constituent quark models

ar X iv : n uc l - th / 9 90 50 04 v 1 4 M ay 1 99 9 Q 2 - Dependence of the Drell - Hearn - Gerasimov integral

The energy and four-momentum (Q 2) dependence of the photo-absorption cross section on the proton is calculated for helicity-1 2 and-3 2 states. An effective Lagrangian model is used, formulated in terms of meson and baryon degrees of freedom, which obeys crossing symmetry, unitarity, Lorentz and gauge invariance. The difference in the cross sections for the two helicity states, the Drell-Hearn...

ar X iv : n uc l - th / 9 70 30 27 v 1 1 2 M ar 1 99 7 f NπN : from quarks to the pion derivative coupling

We study the N πN coupling, in the framework of a QCD-inspired confining Nambu-Jona-Lasinio model. A simple relativistic confining and instantaneous quark model is reviewed. The Salpeter equation for the qqq nucleon and the q ¯ q boosted pion is solved. The f nπn and f nπ∆ couplings are calculated and they turn out to be reasonably good. The sensibility of f nπn and f nπ∆ to confinement, chiral...

ar X iv : n uc l - th / 9 90 50 49 v 1 2 1 M ay 1 99 9 η - and η ′ - meson production in the reaction pn → dM near threshold

ar X iv : n uc l - th / 9 90 50 49 v 2 2 6 M ay 1 99 9 η - and η ′ - meson production in the reaction pn → dM near threshold

ar X iv : n uc l - th / 9 90 60 29 v 3 1 5 Ju l 1 99 9 1 Quark Matter ’ 99 — Theoretical Summary : What Next ?