Speaker
Description
We present a comprehensive study of the electromagnetic form factors (EMFFs) of the pion and kaon, as well as the generalized parton distributions (GPDs) of the pion, using lattice QCD. For the pion and kaon form factors, we compute the pion and kaon EMFFs at high momentum transfers, -t, up to 10 and 28 GeV², respectively, achieving good agreement with experimental results up to -t ≲ 4$ GeV² and providing benchmarks for forthcoming experiments. We also test the QCD collinear factorization framework, relating form factors to meson distribution amplitudes, at next-to-next-to-leading order (NNLO) in perturbation theory. Additionally, we report a lattice calculation of x-dependent pion GPDs at zero skewness with multiple values of momentum transfers. We compare the Lorentz-invariant amplitudes derived from the symmetric and non-symmetric frames, and renormalize the bare matrix elements in the hybrid scheme. The quasi-GPDs can be obtained through the Fourier transform and then matched to the light-cone GPDs utilizing the large momentum effective theory (LaMET) with improved matching, which includes NNLO perturbative corrections, leading renormalon resummation (LRR) as well as renormalization group resummation (RGR). Our results also offer a 3D imaging of the pion in impact-parameter space, providing insights into the internal structure of these fundamental particles.
