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arXiv · 2401.06858

Extracting the Pion Distribution Amplitude from Lattice QCD through Pseudo-Distributions

Daniel Kovner·Joe Karpie·Konstantinos Orginos·Anatoly Radyushkin·Savvas Zafeiropoulos
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Abstract

The Light-Cone Distribution Amplitude (LCDA) encodes the non-perturbative information of the leading Fock component of the hadron wave function, therefore required for processes including exclusive hadron production. As the pseudo-Nambu-Goldstone boson of QCD, the nonperturbative structure of the pion is of particular interest. Progress on the Lattice QCD calculation of the pion LCDA on ${\cal O}(a)$-improved Wilson fermion ensembles at several lattice spacings is presented. Excited-state systematics are taken into account within a Bayesian Model Averaging framework. A Renormalization-Group-Invariant (RGI) ratio of matrix elements is formed for further extraction of the pion LCDA.

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Daniel Kovner, Joe Karpie, Konstantinos Orginos, Anatoly Radyushkin, Savvas Zafeiropoulos. 2024-01-12. Extracting the Pion Distribution Amplitude from Lattice QCD through Pseudo-Distributions. https://arxiv.org/abs/2401.06858

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