Diffractive meson production from virtual photons with odd charge-parity exchange

Abstract

We calculate the cross section of diffractive charge-parity $C=+1$ neutral meson production in virtual photon proton collision at high energies. Due to the opposite $C$ -parities of photon and meson $M^+$ ( $M^+ = \eta_C, \pi^0, a_2$ ) this process probes the $t$ -channel $C=-1$ odderon exchange which is described here as noninteracting three–gluon exchange. Estimates for the cross section of inelastic diffractive process $\gamma^* p\to \eta_C X_p$ are presented. The total cross section of diffractive $\eta_C$ meson photoproduction is found to be 47 pb. The cross sections for the diffractive production of light mesons ( $\pi^0, a_2$ ) in $\gamma^* p$ collisions are of the same order if the photon virtuality $Q^2$ is $ m^2_C$ .