26 July 2026 to 1 August 2026
University of Maryland, College Park
US/Eastern timezone

Proton GPDs from lattice QCD at the physical point

27 Jul 2026, 14:20
20m
Benjamin Banneker A (Adele H. Stamp Student Union)

Benjamin Banneker A

Adele H. Stamp Student Union

3972 Campus Dr, College Park, MD 20742
Contributed talk Structure of hadrons and nuclei Structure of hadrons and nuclei

Speaker

Prof. Martha Constantinou

Description

We present a calculation of the $x$ dependence of quark GPDs for the nucleon using an ensemble of $N_f$=2+1+1 twisted mass clover-improved fermions with masses tuned to their physical values and a lattice spacing of $a=0.080$ fm. We use matrix elements of nonlocal operators at several values of the momentum boost up to 1.69 GeV, enabling the extraction of GPDs in both the large-momentum effective theory (LaMET) and short-distance factorization (SDF). The matrix elements have momentum transfer between the initial and final states and are obtained in an asymmetric kinematic frame, which offers high computational efficiency. The matrix elements are parametrized in terms of eight independent Lorentz-invariant amplitudes, which can then be related to the light-cone GPDs via the quasi-GPDs. The latter are not uniquely defined, and we explore two definitions, one of which is Lorentz invariant. We also discuss the implementation of recent developments in renormalization and $x$-dependence reconstruction. and matching.

Authors

Prof. Martha Constantinou Constantia Alexandrou Simone Bacchio (The Cyprus Institute) Dr Minhuan Chu (Adam Mickiewicz University) Krzysztof Cichy Giannis Koutsou (The Cyprus Institutes) Joshua Miller Gabriele Pierini (The Cyprus Institute, TU Berlin)

Presentation materials