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Connected and leading disconnected hadronic light-by-light contribution to the muon anomalous magnetic moment with physical pion mass

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 نشر من قبل Luchang Jin
 تاريخ النشر 2016
  مجال البحث
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We report a lattice QCD calculation of the hadronic light-by-light contribution to the muon anomalous magnetic moment at physical pion mass. The calculation includes the connected diagrams and the leading, quark-line-disconnected diagrams. We incorporate algorithmic improvements developed in our previous work. The calculation was performed on the $48^3 times 96$ ensemble generated with a physical-pion-mass and a 5.5 fm spatial extent by the RBC and UKQCD collaborations using the chiral, domain wall fermion (DWF) formulation. We find $a_mu^{text{HLbL}} = 5.35 (1.35) times 10^{- 10}$, where the error is statistical only. The finite-volume and finite lattice-spacing errors could be quite large and are the subject of on-going research. The omitted disconnected graphs, while expected to give a correction of order 10%, also need to be computed.



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