T-odd Effects in Photon-Jet Production at the Tevatron

Abstract

The angular distribution in photon-jet production in p\bar{p} -> γjet X is studied within a generalized factorization scheme taking into account the transverse momentum of the partons in the initial hadrons. Within this scheme an anomalously large cos(2ϕ) asymmetry observed in the Drell-Yan process could be attributed to the T-odd, spin and transverse momentum dependent parton distribution function h_1^{\perp q}(x, p_{\perp}^2). The same function is expected to produce a cos(2ϕ) asymmetry in the photon-jet production cross section. This particular azimuthal asymmetry is estimated to be smaller than the Drell-Yan asymmetry but still of considerable size for Tevatron kinematics, offering a new possibility to study T-odd effects at the Tevatron.

4 pages, 3 figures, to appear in the proceedings of 16th International Workshop on Deep-Inelastic Scattering and Related Subjects (DIS2008), London, U.K., 7-11 Apr 2008