2006/04/14 by K. Sasaki, Ken Sasaki, Takahiro Ueda +3 · 1 citation
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1103/physrevd.73.094024
published as Phys.Rev.D73:094024,2006 · 21 pages
arxiv created 2006/04/14 · openalex publication_date 2006/05/25 · arxiv updated 2009/12/01 · openalex created_date 2019/04/25 · openalex updated_date 2026/08/04
We present the next-to-next-to-leading order (\ensuremathα\ensuremathαs2) corrections to the first moment of the polarized virtual photon structure function g1^\ensuremathγ(x,Q2,P2) in the kinematical region \ensuremathΛ2\ensuremath≪P2\ensuremath≪Q2, where \ensuremath-Q2(\ensuremath-P2) is the mass squared of the probe (target) photon and \ensuremathΛ is the QCD scale parameter. In order to evaluate the three-loop-level photon matrix element of the flavor singlet axial current, we resort to the Adler-Bardeen theorem for the axial anomaly and we calculate in effect the two-loop diagrams for the photon matrix element of the gluon operator. The \ensuremathα\ensuremathαs2 corrections are found to be about 3% of the sum of the leading order (\ensuremathα) and the next-to-leading order (\ensuremathα\ensuremathαs) contributions, when Q2=30\ensuremath∼100 GeV2 and P2=3 GeV2, and the number of active quark flavors nf is three to five.