Nonzero transversity distribution of the pion in a quark-spectator-antiquark model -: art. no. 094044

We calculate the nonzero (naive) T-odd transverse momentum dependent transversity distribution h(1)(perpendicular to)(x,k(perpendicular to)(2)) of the pion in a quark-spectator-antiquark model. The final-state interaction is modeled by the approximation of one gluon exchange between the quark and the antiquark spectator. Using our model result we estimate the unsuppressed cos2phi azimuthal asymmetry in unpolarized pi(-)p Drell-Yan process. We find that the transverse momentum dependence of h(1)(perpendicular to)(x,k(perpendicular to)(2)) of the pion is the same as that of h(1)(perpendicular to)(x,k(perpendicular to)(2)) of the proton calculated from the quark-scalar-diquark model, although the x dependencies of them are different from each other. This suggests a connection between cos2phi asymmetries in Drell-Yan processes with different initial hadrons.