| Popis: |
Predictions for the ..pi gamma gamma.. coupling, the pion charge radius , the q/sup 2/ dependence of the pion decay constant near q/sup 2/ = 0 (f/sub ..pi..//sup prime/(0)), and the ratio ..gamma.. describing radiative pion decay are obtained in the context of two related models: the constituent-quark model and a baryon-loop model with n/sub f/ = 2, 3, or 4 flavors. All these models lead to two relations among the four above-mentioned parameters, which are satisfied by the data. A sort of equivalence or duality for the two models is observed, particularly for n/sub f/ = 4. |
