Wigner distributions and orbital angular momentum of a proton

The Wigner distributions for the u and the d quarks in a proton are calculated using the light-front wave functions of the scalar quark-diquark model for a nucleon constructed from the soft-wall AdS/QCD correspondence. We present a detailed study of the quark orbital angular momentum and its correlation with the quark spin and the proton spin. The quark density distributions, considering the different polarizations of quarks and proton, in transverse momentum plane as well as in transverse impact parameter plane are presented for both u and d quarks. (orig.)