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تسجيل مستخدم جديدNonperturbatively-renormalized glue momentum fraction at physical pion mass from Lattice QCD
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We present the first nonperturbatively-renormalized determination of the glue momentum fraction $langle x rangle_g$ in the nucleon, based on lattice-QCD simulations at physical pion mass using the cluster-decomposition error reduction (CDER) technique. We provide the first practical strategy to renormalize the glue energy-momentum tensor (EMT) nonperturbatively in the RI/MOM scheme, and convert the results to the $overline{textrm{MS}}$ scheme with 1-loop matching. The simulation results show that the CDER technique can reduce the statistical uncertainty of its renormalization constant by a factor of ${cal O}$(300) in calculations using typical state-of-the-art lattice volume, and the nonperturbatively-renormalized $langle x rangle_g$ is shown to be independent of the lattice definitions of the glue EMT up to discretization errors. We determine the renormalized $langle x rangle_g^{overline{textrm{MS}}}(2textrm{ GeV})$ to be 0.47(4)(11) at physical pion mass, which is consistent with the experimentally-determined value.
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