Exactly solvable model of a phase transition between hadronic and quark-gluon matter

An exactly solvable model of a phase transition between hadronic and quark-gluon matter is proposed. In the model, the hadronic phase is a gas of bags constructed from point massless constituents. The mass spectrum and volume of these bags is found. Asymptotic expressions are obtained for the thermodynamic functions of the system in the neighborhood of the phase transition point.