Within the large momentum effective theory framework, we report the results of the first direct lattice-QCD 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 Dyson-Schwinger equation. Future calculations at physical pion mass and larger momentum will be able to discern discrepancies in various existing analyses.
Gluon Parton Distribution of the Pion from Lattice QCD
We present the first determination of the x-dependent pion gluon distribution from lattice QCD using the pseudo-PDF 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.
- Award ID(s):
- 1653405
- Publication Date:
- NSF-PAR ID:
- 10249338
- Journal Name:
- Physics letters
- ISSN:
- 0370-2693
- Sponsoring Org:
- National Science Foundation
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