Transversity GPD in photo- and electroproduction of two vector mesons
Résumé
The chiral-odd generalized parton distribution (GPD), or transversity GPD, of the nucleon can be accessed experimentally through the photo- or electroproduction of two vector mesons on a polarized nucleon target, gamma* p --> rho_1^0 rho_2^+ n, where rho_1^0 is produced at large transverse momentum, rho_2+ 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 rho_2+ production. To this end we propose a model for the transversity GPD H_T(x,xi,t), and give an estimate of the relative sizes of the transverse and longitudinal rho_2^+ cross sections. We show that a dedicated experiment at high energy should be able to measure the transversity content of the proton.