Potential models of quarkonium

Quarkonia–bound systems of a heavy quark and an antiquark–are described successfully by nonrelativistic potential models. A review is given of the various phenomenological potentials which have been proposed for the interaction of quarks, their application to the description of all the possible characteristics of charmonium and bottomonium, and the corresponding predictions for the hypothetical toponium. The role of relativistic corrections and nonperturbative effects is discussed briefly.