Nonzero transversity distribution of the pion in a quark-spectator-antiquark model

Abstract

We calculate the nonzero (na\"{\i}ve) T-odd transverse momentum dependent transversity distribution ${h}_{1}^{\ensuremath{\perp}}(x,{\mathbf{k}}_{\ensuremath{\perp}}^{2})$ 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 $\mathrm{cos}2\ensuremath{\phi}$ azimuthal asymmetry in unpolarized ${\ensuremath{\pi}}^{\ensuremath{-}}p$ Drell-Yan process. We find that the transverse momentum dependence of ${h}_{1}^{\ensuremath{\perp}}(x,{\mathbf{k}}_{\ensuremath{\perp}}^{2})$ of the pion is the same as that of ${h}_{1}^{\ensuremath{\perp}}(x,{\mathbf{k}}_{\ensuremath{\perp}}^{2})$ 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 $\mathrm{cos}2\ensuremath{\phi}$ asymmetries in Drell-Yan processes with different initial hadrons.

Locations

• Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D, Particles, fields, gravitation, and cosmology - View
• arXiv (Cornell University) - View - PDF
• DataCite API - View