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arXiv · 1603.05256

Glue Spin of the Proton

Yi-Bo Yang·Raza Sabbir Sufian·Andrei Alexandru·Terrence Draper·Michael J. Glatzmaier·Keh-Fei Liu
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Abstract

We report the progress on the lattice QCD calculation of the glue spin contribution to proton spin. This calculation is carried out with valence overlap fermion on 2+1 flavor DWF gauge configurations at two lattice spacings with the momentum of the frame in the kinematic range $0\leq p^2 \leq 2$ GeV$^2$. A mild frame dependence is observed. The matching and mixing with large-momentum effective field theory are in progress. The unrenormalized result at $p^2=4$ GeV$^2$ with $O(a^2)$ correction gives $S_G$ = 0.13(3).

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Yi-Bo Yang, Raza Sabbir Sufian, Andrei Alexandru, Terrence Draper, Michael J. Glatzmaier, Keh-Fei Liu. 2016-03-16. Glue Spin of the Proton. https://arxiv.org/abs/1603.05256

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