Lattice Nucleon Isovector Unpolarized Parton Distribution in the Physical-Continuum Limit

Understand

We present the first lattice-QCD calculation of the nucleon isovector unpolarized parton distribution functions (PDFs) at the physical-continuum limit using Large-Momentum Effective Theory (LaMET).

• The lattice results are calculated using ensembles with multiple sea pion masses with the lightest one around 135~MeV, 3 lattice spacings $a\in[0.06,0.12]$~fm, and multiple volumes with $M_\pi L$ ranging 3.3 to 5.5.
• We perform a simultaneous chiral-continuum extrapolation to obtain RI/MOM renormalized nucleon matrix elements with various Wilson-link displacements in the continuum limit at physical pion mass.
• Then, we apply one-loop perturbative matching to the quasi-PDFs to obtain the lightcone PDFs.