Generalized parton distributions (GPDs) are key quantities for the description of a hadron’s three-dimensional structure. They are the current focus of all areas of hadronic physics—phenomenological, experimental and theoretical, including lattice QCD. Synergies between these areas are desirable and essential to achieve precise quantification and understanding of the structure of, particularly, nucleons, as the basic ingredients of matter. In this paper, we investigate, for the first time, the numerical implementation of the pseudodistribution approach for the extraction of zero-skewness GPDs for unpolarized quarks. Pseudodistributions are Euclidean parton correlators computable in lattice QCD that can be perturbatively matched to the light-cone parton distributions of interest. Although they are closely related to the quasidistributions and come from the same lattice-extracted matrix elements, they are, however, subject to different systematic effects. We use the data previously utilized for quasi-GPDs and extend it with other momentum transfers and nucleon boosts, in particular a higher one ( ) with eightfold larger statistics than the largest one used for quasidistributions ( ). We renormalize the matrix elements with a ratio scheme and match the resulting Ioffe time distributions to the light cone in coordinate space. The matched distributions are then used to reconstruct the dependence with a fitting . We investigate some systematic effects related to this procedure, and we also compare the results with the ones obtained in the framework of quasi-GPDs. Our final results involve the invariant four-momentum transfer squared ( ) dependence of the flavor nonsinglet ( ) and GPDs.
Bhattacharya, Shohini, et al. "Generalized parton distributions from the pseudodistribution approach on the lattice." Physical Review. D., vol. 110, no. 5, Sep. 2024. https://doi.org/10.1103/PhysRevD.110.054502
Bhattacharya, Shohini, Cichy, Krzysztof, Constantinou, Martha, Metz, Andreas, Nurminen, Niilo, & Steffens, Fernanda (2024). Generalized parton distributions from the pseudodistribution approach on the lattice. Physical Review. D., 110(5). https://doi.org/10.1103/PhysRevD.110.054502
Bhattacharya, Shohini, Cichy, Krzysztof, Constantinou, Martha, et al., "Generalized parton distributions from the pseudodistribution approach on the lattice," Physical Review. D. 110, no. 5 (2024), https://doi.org/10.1103/PhysRevD.110.054502
@article{osti_2439295,
author = {Bhattacharya, Shohini and Cichy, Krzysztof and Constantinou, Martha and Metz, Andreas and Nurminen, Niilo and Steffens, Fernanda},
title = {Generalized parton distributions from the pseudodistribution approach on the lattice},
annote = { Generalized parton distributions (GPDs) are key quantities for the description of a hadron’s three-dimensional structure. They are the current focus of all areas of hadronic physics—phenomenological, experimental and theoretical, including lattice QCD. Synergies between these areas are desirable and essential to achieve precise quantification and understanding of the structure of, particularly, nucleons, as the basic ingredients of matter. In this paper, we investigate, for the first time, the numerical implementation of the pseudodistribution approach for the extraction of zero-skewness GPDs for unpolarized quarks. Pseudodistributions are Euclidean parton correlators computable in lattice QCD that can be perturbatively matched to the light-cone parton distributions of interest. Although they are closely related to the quasidistributions and come from the same lattice-extracted matrix elements, they are, however, subject to different systematic effects. We use the data previously utilized for quasi-GPDs and extend it with other momentum transfers and nucleon boosts, in particular a higher one ( P 3 = 1.67 GeV ) with eightfold larger statistics than the largest one used for quasidistributions ( P 3 = 1.25 GeV ). We renormalize the matrix elements with a ratio scheme and match the resulting Ioffe time distributions to the light cone in coordinate space. The matched distributions are then used to reconstruct the x dependence with a fitting . We investigate some systematic effects related to this procedure, and we also compare the results with the ones obtained in the framework of quasi-GPDs. Our final results involve the invariant four-momentum transfer squared ( − t ) dependence of the flavor nonsinglet ( u − d ) H and E GPDs. Published by the American Physical Society 2024 },
doi = {10.1103/PhysRevD.110.054502},
url = {https://www.osti.gov/biblio/2439295},
journal = {Physical Review. D.},
issn = {ISSN 2470-0010},
number = {5},
volume = {110},
place = {United States},
publisher = {American Physical Society},
year = {2024},
month = {09}}
Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)
Sponsoring Organization:
USDOE Laboratory Directed Research and Development (LDRD) Program; USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), Nuclear Physics (NP)