P. J. S. Watson

SU(3) string-flip potential models and nuclear matter

Abstract A Monte Carlo model for nuclear matter using a many-body SUc(3) string-flip potential, with fixed colour, is investigated. The potential is approximated by considering colour-singlet flux-tube formations that connect only three quarks at a time. The model is compared with a similar string-flip model, proposed by Horowitz and Piekarewicz [1], that approximates higher-order flux-tube formations by connecting quarks in colour-singlet chains. The former model gives an EMC nucleon “swelling” effect, whereas the latter gives an opposite effect. Possible discrepancies between the two models are discussed.

Flux-bubble models and mesonic molecules

Abstract It has been shown that the string-flip potential model reproduces most of the bulk properties of nuclear matter, with the exception of nuclear binding. Furthermore, it was postulated that this model with the inclusion of the colour-hyperfine interaction should produce binding. In some recent work a modified version of the string-flip potential model was developed, called the flux-bubble model, which would allow for the addition of perturbative QCD interactions. In attempts to construct a simple q q nucleon system using the flux-bubble model (which only included colour-Coulomb interactions) difficulties arise with trying to construct a many-body variational wave function that would take into account the locality of the flux-bubble interactions. In this paper we look at a toy system, a mesonic molecule, in order to understand these difficulties. En route, a new variational wave function is proposed that may have a sufficient impact on the old string-flip potential model results that the inclusion of perturbative effects may not be needed.

Oersted states: the quantum mechanics of a particle interacting with a superconducting string

Abstract We consider a charged particle interacting with a current-carrying filament. As expected from a general argument, there are no stationary states. However, quasi-bound states can be formed, and the properties of these are discussed. The spectrum of the emitted radiation is described. The relevance to both laboratory experiments and superconducting cosmic strings is discussed.