Description
Title:
Exploring Meson Structure via Lattice QCD: Electromagnetic Form Factors and Generalized Parton Distributions
Abstract:
We present a comprehensive lattice QCD study of meson internal structure through electromagnetic form factors (EMFFs) and generalized parton distributions (GPDs). Utilizing gauge ensembles with physical pion masses, we calculate EMFFs at unprecedentedly high momentum transfers up to $10 \text{ GeV}^2$ for the pion and $28 \text{ GeV}^2$ for the kaon. Our results demonstrate good agreement with available experimental data, providing critical ab-initio benchmarks for upcoming high-energy experiments while enabling a test of the QCD factorization framework. Furthermore, we report a state-of-the-art calculation of $x$-dependent valence pion GPDs at zero skewness. By employing a hybrid renormalization scheme within the Large Momentum Effective Theory (LaMET) framework and incorporating advanced perturbative matching, we extract light-cone GPDs with high precision across multiple momentum transfers. Finally, we present 3D tomographic images of the pion in impact-parameter space. This work highlights the power of lattice QCD in resolving the multi-dimensional structure of hadrons.
This talk is based on:
[1] Phys. Rev. Lett. 133 (2024) 181902 [arXiv:2404.04412]
[2] JHEP 02 (2025) 056 [arXiv:2407.03516]
Brief introduction about the speaker:
Qi Shi is a Postdoctoral Scholar in the Physics Department at Kent State University. She earned her Ph.D. in Physics from Central China Normal University in 2025 , having conducted research as a Visiting Scholar at Brookhaven National Laboratory (BNL) from 2022 to 2025. Her research specializes in large-scale numerical simulations of Lattice QCD to investigate hadron structures, focusing on Generalized Parton Distributions (GPDs), Parton Distribution Functions (PDFs), and electromagnetic form factors (EMFFs). Her pioneering work on meson EMFFs at large momentum transfer was published in Physical Review Letters and honored as one of Brookhaven’s Top 10 Discoveries of 2024. As a Principal Investigator, she has been awarded the NERSC DOE Mission Science allocations for two consecutive years (2025–2026) for her projects on pion and nucleon GPDs.
