Hadron spectroscopy with instanton induced quark forces

Abstract

It is shown that within the framework of a non-relativistic quark model with string-like confinement and an instanton induced residual quark-quark interaction it is possible to account simultaneously for the baryon and the meson spectra, including the 7r-q-t/' splitting for pseudoscalar mesons, up to energies of roughly 2 GeV.

Casimir scaling, glueballs, and hybrid gluelumps

“…The raise of degeneracy between spin 0 and spin 1 mesons can be due to a spin-spin potential coming from the OGE or due to an instanton induced interaction [30,31]. For spin 1 mesons, the spin-dependent interaction is small in the former case or vanishing in the latter case.…”

Baryons as relativistic three-quark bound states

“…For hyperons this is not the case, and thus one has to conclude that, if the picture of mutually interacting constituents quarks is a good description of reality, these interactions are flavour dependent. In particular, such interactions can be motivated as instanton-induced forces [133][134][135], or spin-spin forces via one-boson exchange [22,136,137].…”

Electromagnetic splitting for mesons and baryons using dressed constituent quarks

“…The resulting spectra of these models are in correct agreement with experimental data. However, it seems very difficult to get, in a unified scheme (same form of the potential and same set of parameters), a good description of both meson and baryon properties [16,17]. For example in the well known works of Isgur [14,15], the string tension is different in the mesonic and baryonic sectors.…”

“…It is completely phenomenological and one can consider that the dressing of the quarks is included and simulated in the value of the various parameters. The second one (BSS) starts with more fundamental QCD grounds and is based on instanton induced effects [16,33]; the dressing is explicitly taken into account but there remain nevertheless some free parameters that are adjusted on the spectra.…”