Speaker
Description
Mapping the 3D structure of the proton in terms of its spinning quark and gluon constituents is one of the main goals of current hadronic physics investigations. Generalized parton distributions can provide part of the solution, connecting through Fourier transformation to the single particle spatial density of quarks and gluons with a given longitudinal momentum fraction, x. The physical properties derived from GPDs are the average radius of each partonic component of the proton/neutron and quantities derived from it. A fuller dynamical picture of the proton's interior can be, however, captured by introducing two-particle spatial density distributions. The latter
render the relative position of quarks and gluons with respect to one another in the transverse plane, providing a measure of the amount of correlations in the particles' motion. We show that two-particle densities can be de?ned in QCD introducing the concept of generalized double parton distributions (GDPDs) and provide data informed scenarios on the geometric structure of the proton including the relative positions of gluons around valence quarks inside the proton.
