Hadronic light-by-light corrections to the muon g-2: The pion-pole contribution
Abstract
The correction to the muon anomalous magnetic moment from the pion-pole contribution to the hadronic light-by-light scattering is considered using a description of the π0-γ*-γ* transition form factor based on the large-NC and short-distance properties of QCD. The resulting two-loop integrals are treated by first performing the angular integration analytically, using the method of Gegenbauer polynomials, followed by a numerical evaluation of the remaining two-dimensional integration over the moduli of the Euclidean loop momenta. The value obtained, aLbyLπ0μ=+5.8(1.0)×10-10, disagrees with other recent calculations. In the case of the vector meson dominance form factor, the result obtained by following the same procedure reads aLbyLπ0μ\|VMD=+5.6×10-10, and differs only by its overall sign from the value obtained by previous authors. The inclusion of the η and η' poles gives a total value aLbyLPSμ=+8.3(1.2)×10-10 for the three pseudoscalar states. This result substantially reduces the difference between the experimental value of aμ and its theoretical counterpart in the standard model.
- Publication:
-
Physical Review D
- Pub Date:
- April 2002
- DOI:
- 10.1103/PhysRevD.65.073034
- arXiv:
- arXiv:hep-ph/0111058
- Bibcode:
- 2002PhRvD..65g3034K
- Keywords:
-
- 13.40.Em;
- 12.38.Lg;
- 14.40.Aq;
- 14.60.Ef;
- Electric and magnetic moments;
- Other nonperturbative calculations;
- pi K and eta mesons;
- Muons;
- High Energy Physics - Phenomenology;
- High Energy Physics - Experiment
- E-Print:
- 27 pages, Latex, 3 figures. v2: version to be published in Phys. Rev. D, Note added and references updated (don't worry, sign has not changed)