Strong coupling constant and four-quark condensates from vacuum polarization functions with dynamical overlap fermions
نویسندگان
چکیده
We study the vacuum polarization functions on the lattice with exact chiral symmetry of overlap fermion by matching the lattice data at large momentum scales with the Operator Product Expansion (OPE). We extract the strong coupling constant α s (µ) in two-flavor QCD as Λ (2) MS = 0.234(9)(+16 − 0) GeV. From the analysis of the difference between the vector and axial-vector channels , we extract some of the four-quark (dimension-six) condensates. c Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike Licence.
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