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Enhancement of Radiatively Induced Magnetic Moment Form-Factors of Muon: an Effective Lagrangian Approach

Martti Raidal
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Abstract

Using an effective lagrangian approach, we identify a class of models in which the loop-induced magnetic moment form-factors of muon are enhanced by possibly large factors (Λ^2_F/Λ^2)(m_τ/m_μ)\ln(m_τ^2/Λ^2) or (Λ^2_F/Λ^2)\ln(m_μ^2/Λ^2), where Λis the scale of new physics and Λ_F is the Fermi scale. These follow from left- and right-chirality mixing dimension-8 operators which for relatively small Λ, as required to explain the new (g_μ-2) measurement, dominate over dimension-6 operators. Thus significant enhancement of new physics contributions to (g_μ-2) and, in the presence of intergenerational couplings, also to the μ\to eγdecay rate is possible. We discuss the compatibility of the (g_μ-2) and μ\to eγexperimental data in this case and comment on the enhancement of the electron anomalous magnetic moment. An explicit model is presented to illustrate the general results.

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Martti Raidal. 2001-04-15. Enhancement of Radiatively Induced Magnetic Moment Form-Factors of Muon: an Effective Lagrangian Approach. https://doi.org/10.1016/s0370-2693(01)00504-4

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