The cos 2 phi asymmetry of Drell-Yan and J/psi production in unpolarized ppbar scattering

Abstract

We investigate the cos 2 phi azimuthal asymmetry in Drell--Yan and J/psi production from unpolarized ppbar scattering at GSI-HESR energies. The contribution to this asymmetry arising from the leading-twist Boer-Mulders function h_1^perp(x, k_T^2), which describes a correlation between the transverse momentum and the transverse spin of quarks in an unpolarized hadron, is explicitly evaluated, and predictions for the GSI-HESR kinematic regime are presented. We show that the cos 2 phi asymmetry is quite sizable both on the J/psi peak and in the Drell-Yan continuum region. Therefore these processes may offer an experimentally viable access to the Boer-Mulders function in the early unpolarized stage of GSI experiments.

5 pages, 3 figures, to be published in Eur. Phys. J

References in corpus (1)

• Transversity distribution function in hard scattering of polarized protons and antiprotons in the PAX experiment

Cited by in corpus (3)

• A systematic phenomenological study of the $\cos 2\varphi$ asymmetry in unpolarized semi--inclusive DIS
• T-odd effects in photon-jet production at the Tevatron
• On duality of Drell-Yan and J/psi production processes