We present the first determination of the xdependent pion gluon distribution from lattice QCD using the pseudoPDF approach. We use lattice ensembles with 2+1+1 flavors of highly improved staggered quarks (HISQ), generated by MILC Collaboration, at two lattice spacings a≈0.12 and 0.15~fm and three pion masses Mπ≈220, 310 and 690 MeV. We use clover fermions for the valence action and momentum smearing to achieve pion boost momentum up to 2.29 GeV. We find that the dependence of the pion gluon parton distribution on lattice spacing and pion mass is mild. We compare our results from the lightest pion mass ensemble with the determination by JAM and xFitter global fits.
Direct latticeQCD calculation of pion valence quark distribution
Within the large momentum effective theory framework, we report the results of the first direct latticeQCD calculation of the valence quark distribution in the pion. Our results are comparable quantitatively with the results extracted from experimental data as well as from DysonSchwinger equation. Future calculations at physical pion mass and larger momentum will be able to discern discrepancies in various existing analyses.
 Award ID(s):
 1653405
 Publication Date:
 NSFPAR ID:
 10097099
 Journal Name:
 The 36th Annual International Symposium on Lattice Field Theory (LATTICE2018)
 Volume:
 334
 Page Range or eLocationID:
 108
 Sponsoring Org:
 National Science Foundation
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