Quark Orbital Angular Momentum from Lattice QCD
نویسندگان
چکیده
employs the Z2 noise with an unbiased subtraction. This reduced the error by a factor of 4 with negligible overhead. The total quark contribution to the proton spin is found to be 0.30±0.07. From this and the quark spin content we deduce the quark orbital angular momentum to be 0.17 ± 0.06 which is ∼ 34% of the proton spin. We further predict that the gluon angular momentum to be 0.20 ± 0.07, i. e. ∼ 40% of the proton spin is due to the glue.
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