Quark-gluon correlations in the twist-3 TMD using light-front wave functions

We discuss a T-even, twist-3 transverse momentum dependent parton distribution for unpolarized proton. We review its general, model-independent and gauge-independent decomposition, which follows from the QCD equations of motion and it is given in terms of a lower-twist distribution, a pure twist-3 distribution and singular terms. Then we present the results for the twist-3 distribution, using a Light-Front Wave Function (LFWF) overlap representation and taking into account the contribution from the three-quark and the three-quark plus a gluon proton’s Fock-states. Predictions are obtained using a model for the LFWFs, based on the conformal expansion of the proton distribution amplitudes. The parameters of the LFWFs are fixed to reproduce phenomenological parametrizations of the collinear twist-2 unpolarized parton distribution