Exchange mechanism for π + p→ N *++ ρ 0 reaction at 2.75 GeV/c *++ ρ 0 reaction at 2.75 GeV/c

The reaction π+p→pπ+π+π− has been studied, particularly the channel π+p→N*+++ρ0. Experimental decay angular distributions ofN*++ and ρ0 resonances indicate that the production is dominated by the O.P.E. model. Nevertheless the experimental differential cross-section is not in agreement with the theoretical predictions, even if absorption effects are taken into accont.