TMDs: Towards a Synergy between Lattice QCD and Global Analysis

Transversity PDF of the proton from lattice QCD with physical quark masses

22 Jun 2023, 15:00

30m

Center for Frontiers in Nuclear Science, Stony Brook University

Session III

Speaker

Xiang Gao

Description

The transversity PDFs, which describe the difference between probabilities to find a parton spin aligned and anti-aligned to the transversely polarized parent nucleon, is considerably less constrained from experiments due to their chiral-odd nature. Complementary information from lattice QCD is desired. In this talk, we report a calculation using a $N_f=2+1$ HISQ ensemble with physical-mass quarks and a lattice spacing of $a=0.076$ fm. Applying short distance factorization to the ratio-scheme renormalized bi-local matrix elements of nucleon boosted up to 1.5 GeV, we extract the first few Mellin moments and reconstruct the Bjorken-x dependence using a deep neural network (DNN).  We also present the results from large-momentum effective theory approach utilizing a hybrid renormalization scheme.

Presentation materials

Transversity_XG.pdf