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<pre wrap="">Theory Center Seminar
Monday, January 30, 2017
1:00 p.m. (coffee at 12:45 p.m.)
CEBAF Center, Room L102
Anatoly Radyushkin
ODU/JLab
<b>Nonperturbative Evolution of Parton Quasi-Distributions</b>
Using the formalism of parton virtuality distribution functions (VDFs) we establish a connection between the transverse momentum dependent distributions (TMDs) and quasi-distributions (PQDs) introduced recently by X. Ji for lattice QCD extraction of parton distributions. We build models for PQDs from the VDF-based models for soft TMDs, and analyze the P_z dependence of the resulting PQDs. We observe a strong nonperturbative evolution of PQDs for small and moderately large values of P_z reflecting the transverse momentum dependence of TMDs. Thus, the study of PQDs on the lattice in the domain of strong nonperturbative effects opens a new perspective for investigation of the 3-dimensional hadron structure. A similar analysis is done for the pion distribution amplitude. As there are many models claimed to describe the primordial shape of the pion DA, we present the $p_3$-evolution patterns for models producing some popular proposals: Chernyak-Zhitnitsky, flat and asymptotic DAs! Our results may be used as a guide for future studies of the pion distribution amplitude on the lattice using the quasi-distribution approach.</pre>
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