A multipole expansion of the color gauge field is shown to yield selection rules and rate estimates for hadronic transitions between nonrelativistic quark-antiquark bound states. The non-Abelian character of the field is of critical importance in determining the selection rules for the leading ("allowed") transition.

• Received 20 December 1977

DOI:https://doi.org/10.1103/PhysRevLett.40.598