Hadronic LightByLight Scattering Contribution to the Muon g  2: An Effective Field Theory Approach
Abstract
The hadronic lightbylight contribution to a_{μ}, the anomalous magnetic moment of the muon, is discussed from the point of view of an effective lowenergy theory. As an application, the coefficient of the leading logarithm arising from the twoloop graphs involving two anomalous vertices is computed, and found to be positive. This corresponds to a positive sign for the pionpole contribution to the hadronic lightbylight correction to a_{μ}, and to a sizable reduction of the discrepancy between the present experimental value of a_{μ} and its theoretical counterpart in the standard model.
 Publication:

Physical Review Letters
 Pub Date:
 February 2002
 DOI:
 10.1103/PhysRevLett.88.071802
 arXiv:
 arXiv:hepph/0111059
 Bibcode:
 2002PhRvL..88g1802K
 Keywords:

 High Energy Physics  Phenomenology;
 High Energy Physics  Experiment
 EPrint:
 4 pages, 1 figure. v2: published version