Abstract
We report the first lattice QCD calculation of the glue spin in the nucleon. The lattice calculation is carried out with valence overlap fermions on flavor domain-wall fermion gauge configurations on four lattice spacings and four volumes including an ensemble with physical values for the quark masses. The glue spin in the Coulomb gauge in the modified minimal subtraction () scheme is obtained with one-loop perturbative matching. We find the results fairly insensitive to lattice spacing and quark masses. We also find that the proton momentum dependence of in the range is very mild, and we determine it in the large-momentum limit to be at the physical pion mass in the scheme at . If the matching procedure in large-momentum effective theory is neglected, is equal to the glue helicity measured in high-energy scattering experiments.
- Received 12 October 2016
DOI:https://doi.org/10.1103/PhysRevLett.118.102001
© 2017 American Physical Society
Physics Subject Headings (PhySH)
Viewpoint
Spinning Gluons in the Proton
Published 6 March 2017
Computer simulations indicate that about 50% of the proton’s spin comes from the spin of the gluons that bind its quark constituents.
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