Soliton bag models of hadrons from QCD

Several phenomenological models of hadrons are derived from quantum chromodynamics (QCD). Functional-integral methods are used to obtain an approximate bilocal-field representation of the QCD generating functional. The degenerate vacuum configurations of the action for the bilocal fields have a rich topological structure arising from the dynamically broken chiral symmetry. Restricting the bilocal-field fluctuations to those of local fields results in a local-field bosonization of QCD, from which we obtain values for several meson parameters. A nontopological-soliton ansatz for hadronic states leads to a generalized bag-model action which as special cases contains the chiral-bag-model action and the MIT-bag-model action. All parameters in these actions are calculable and in particular the MIT bag constant is calculated. This work extends our previous calculation of the bag constant