Speaker
Description
We report the first nucleon gluon parton distribution function (PDF) using Large-Momentum Effective Theory (LaMET). We compute the matching coefficients for the gluon operator with the best signal to perform hybrid-renormalization and matching to the lightcone at the one-loop level. We demonstrate that with the proper Wilson coefficients in place, the counterterms for the renormalization are independent of the hadron and mass within statistical error. Using the resulting renormalization, we then compute the nucleon PDF using a HISQ ensemble generated by the MILC collaboration with $N_f = 2 + 1 + 1$, $a \approx 0.12$ fm, with valence pion masses of 310 and 690 MeV and two gauge link smearing techniques. Despite the physics effects of the heavier than physical pion masses and gauge link smearing, this calculation provides excellent proof of principle and compares reasonably with selected global fit results. We also report on preliminary results towards computing the gluon PDF from Coulomb gauge fixed correlators.
