Chiral symmetry and the delta-nucleon transition form factors - art. no. 054022

The three complex form factors entering the Delta-->N gamma* vertex are cal culated to O(epsilon(3)) in the framework of a chiral effective theory with explicit Delta(1232) degrees of freedom included. It is shown that the low q(2) behavior of the form factors is governed by pi N, pi Delta loop effec ts. Predictions are given for the q(2) dependence of the three transition m ultipoles M1(q(2)), E2(q(2)), C2(q(2)). Furthermore, the role of the presen tly unknown low energy constants that affect the values of the multipole ra tios EMR(q(2)) and CMR(q(2)) is elucidated. [S0556-2821(99)04215-0].