Transversity GPD in photoproduction and electroproduction of two vector mesons

The chiral-odd generalized parton distribution (GPD), or transversity GPD, of the nucleon can be accessed experimentally through the photoproduction or electroproduction of two vector mesons on a polarized nucleon target, γ(*)N→ρ1ρ2N’, where ρ1 is produced at large transverse momentum, ρ2 is transversely polarized, and the mesons are separated by a large rapidity gap. We predict the cross section for this process for both transverse and longitudinal ρ2 production. To this end, we propose a model for the transversity GPD HT(x,ξ,t) and give an estimate of the relative sizes of the transverse and longitudinal ρ2 cross sections. We show that a dedicated experiment at high energy should be able to measure the transversity content of the proton.