Parton distribution functions (PDFs) are central to precision QCD phenomenology. Their Mellin moments can be computed on the lattice, but direct determinations using local operators, besides ⟨x⟩, face severe challenges from reduced hypercubic symmetry, limiting results to the lowest moments. A recently proposed method resolves these issues using gradient flow. We demonstrate the efficacy of this method by computing ratios of flavor nonsinglet pion PDF moments up to ⟨x⁵⟩ on four lattice spacings at m_π ≃ 411 MeV. The moments and reconstructed PDF agree quantitatively with recent phenomenological extractions.

Authors:

김장호 (서울대학교), Andrea Shindler (RWTH Aachen University), Dimitra A. Pefkou (Lawrence Berkeley National Laboratory), André Walker-Loud (Lawrence Berkeley National Laboratory), Anthony Francis, Patrick Fritzsch, Robert V. Harlander, Rohith Karur, Jonas T. Kohnen, Giovanni Pederiva, Antonio Rago, Savvas Zafeiropoulos (OpenLat Collaboration)

Links:

Physical Review Letters https://doi.org/10.1103/z3wr-zk8n

Physical Review D https://doi.org/10.1103/vw4v-nyvw