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Heavy mass expansion, light-by-light scattering and the anomalous magnetic moment of the muon

J. H. Kühn·A. I. Onishchenko·A. A. Pivovarov·O. L. Veretin
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Abstract

Contributions from light-by-light scattering to (g_μ-2)/2, the anomalous magnetic moment of the muon, are mediated by the exchange of charged fermions or scalar bosons. Assuming large masses M for the virtual particles and employing the technique of large mass expansion, analytical results are obtained for virtual fermions and scalars in the form of a series in (m_μ/M)^2. This series is well convergent even for the case M=m_μ. For virtual fermions, the expansion confirms published analytical formulae. For virtual scalars, the result can be used to evaluate the contribution from charged pions. In this case our result confirms already available numerical evaluations, however, it is significantly more precise.

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J. H. Kühn, A. I. Onishchenko, A. A. Pivovarov, O. L. Veretin. 2003-01-19. Heavy mass expansion, light-by-light scattering and the anomalous magnetic moment of the muon. https://doi.org/10.1103/physrevd.68.033018

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