Partonic structure of nucleons and nuclei

M. Polyakov (RUB) / Y. Dong (IHEP)

Since October 2021 E. Epelbaum (RUB) / Y. Dong (IHEP)

A study of the generalized parton distributions (GPDs) can give a 3-dimensional imaging of the
nucleon internal structures, since the GPDs encode the information of the nucleon form factors as
well as the parton distributions inside the system simultaneously. In the new funding period we plan
to concentrate on the mechanical properties (pressure and shear forces distributions) inside
hadrons encoded in the gravitational form factors (GFFs). The gravitational form factors are related
to a very wide class of physics problems ranging from the fundamental questions of General
Relativity to the theory of hard exclusive processes and physics of exotic charmonia. Although a
direct access to these form factors with gravitational forces is out of reach, their first
measurements, following the theory suggested by one of the PLs in hard QCD processes became
available.