Diffractive production of ρ-mesons and of ρπ-systems by neutrinos and antineutrinos on protons

Evidence is presented for diffractive production of ρ-mesons and of ρπ-systems invp and\(\bar \nu p\) chargedcurrent interactions. In the (anti-)neutrino energy range 10 GeVdiffractive ρ and diffractive ρπ production are found to be (0.64±0.14 (stat.)±0.08 (syst.))% and (0.28±0.08 (stat.)±0.04 (syst.))% of the charged-current cross section. The diffractive ρπ signal is consistent with being entirely due to diffractivea1 production. However, the data cannot distinguish between diffractivea1 and diffractive nonresonant ρπ production. The experimental distributions ofW, Q2,x Bj andy Bj for diffractive ρ and ρπ events are consistent with model predictions.