The anomalous gamma -> pi^+ pi^0 pi^- form factor and the light-quark mass functions at low momenta

Abstract

The gamma -> 3 pi form factor was calculated in a simple-minded constituent model with a constant quark mass parameter, as well as in the Schwinger-Dyson approach. The comparison of these and various other theoretical results on this anomalous process, as well as the scarce already available data (hopefully to be supplemented by more accurate CEBAF data), seem to favor Schwinger-Dyson modeling which would yield relatively small low-momentum values of the constituent (dynamically dressed) quark mass function.