We investigate the quark Wigner distributions in a light-cone spectator model. The Wigner distribution, as a quasidistribution function, provides the most general one-parton information in a hadron. Combining the polarization configurations, unpolarized, longitudinal polarized, or transversal polarized, of the quark and the proton, we can define 16 independent Wigner distributions at leading twist. We calculate all these Wigner distributions for the $u$ quark and the $d$ quark, respectively. In our calculation, both the scalar and the axial-vector spectators are included, and the Melosh–Wigner rotation effects for both the quark and the axial-vector spectator are taken into account. The results provide us a very rich picture of the quark structure in the proton.

• Received 31 March 2014

DOI:https://doi.org/10.1103/PhysRevD.91.034019