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arXiv · hep-ph/9501253

Electroweak instantons at non-zero Weinberg angle

M. J. Gibbs
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Abstract

Previous calculations of instanton effects in electroweak theory have concentrated on the case of zero Weinberg angle $θ_w$, where the U(1) hypercharge field decouples. In this paper we extend the instanton calculation to non-zero $θ_w$, by constructing a perturbation expansion. This allows for the first time the study of photon production at B and L number violating verticies. We find that the orientation of the instanton solution in isospin space has to be carefully considered to avoid unphysical results.

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M. J. Gibbs. 1995-01-10. Electroweak instantons at non-zero Weinberg angle. https://doi.org/10.1016/0370-2693(95)00126-6

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