Diffractive production of the A2 and its implications

We study diffractive production of the A2 resonance in the context of a unitarity-corrected Deck production amplitude for πp → (rhoπ) p. After projecting the D-wave rhoπ production amplitudes from the Deck model with π and rho exchange terms, we include rhoπ final-state rescattering corrections. This corrected Deck amplitude fails to describe the A2 data in both shape and absolute cross section. To reproduce the data, we require a dominant direct spin-flip coupling of the Pomeron at the πA2 production vertex, in contradiction with the s-channel helicity and Gribov-Morrison phenomenological rules for diffraction