Quark Wigner Distributions and Orbital Angular Momentum

Understand

We study the Wigner functions of the nucleon which provide multidimensional images of the quark distributions in phase space.

• These functions can be obtained through a Fourier transform in the transverse space of the generalized transverse-momentum dependent parton distributions.
• They depend on both the transverse position and the three-momentum of the quark relative to the nucleon, and therefore combine in a single picture all the information contained in the generalized parton distributions and the transverse-momentum dependent parton distributions.
• We focus the discussion on the distributions of unpolarized/longitudinally polarized quark in an unpolarized/longitudinally polarized nucleon.