Glue Spin of the Proton

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 $0\le p^2\le 2$ 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).

Comments: Talk presented at the 33nd International Symposium on Lattice Field Theory, 24-30 July, 2015, Kobe, Japan. 7 pages, 4 figures, references updated