  We first describe a new way to access the chiral odd transversity parton
distribution in the proton through the photoproduction of lepton pairs. The
basic ingredient is the interference of the usual Bethe-Heitler or Drell-Yan
amplitudes with the amplitude of a process, where the photon couples to quarks
through its chiral-odd distribution amplitude, which is normalized to the
magnetic susceptibility of the QCD vacuum. We also show how the chiral-odd
transversity generalized parton distributions (GPDs) of the nucleon can be
accessed experimentally through the exclusive electro - or photoproduction
process of a meson pair with a large invariant mass and when the final nucleon
has a small transverse momentum. We calculate perturbatively the scattering
amplitude at leading order, both in the high energy domain which may be
accessed in electron-ion colliders and in the medium energy range. Estimated
rates are encouraging.
