Eur. Phys. J. C (2006) 47: 87-94
https://doi.org/10.1140/epjc/s2006-02545-3

Theoretical Physics

Transversity GPD in photoproduction and electroproduction of two vector mesons

¹ CPhT, École Polytechnique, 91128, Palaiseau, France
² Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
³ Sołtan Institute for Nuclear Studies, Hoża 69, 00-681, Warsaw, Poland
⁴ Université de Liège, 4000, Liège, Belgium
⁵ LPT, Université Paris-Sud, 91405, Orsay, France

^* e-mail: REnberg@lbl.gov

Received: 18 January 2006
Revised: 11 March 2006
Published online: 20 April 2006

Abstract

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 H_T(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.