Beyond the Standard Model contributions to dipole moments

Nicola Valori; Oscar Vives

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arXiv · 2505.06345

Beyond the Standard Model contributions to dipole moments

Nicola Valori·Oscar Vives

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Abstract

The goal of this work is to provide a pedagogical introduction to dipole moments and dipole transitions in theories beyond the Standard Model, with a focus on the lepton sector. We emphasize the exceptional sensitivity of dipole observables to new physics, analyzing the most sensitive processes, such as the muon anomalous magnetic moment, the electric dipole moment of the electron, and the branching ratio $\text{BR}(\mu \to e \gamma)$. This review is intended for PhD students, early-career researchers, and anyone entering the field for the first time. It does not aim to provide a complete overview of all models in the literature, but rather to serve as an accessible guide, using simple and representative examples from the most well-studied extensions of the Standard Model.

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Nicola Valori, Oscar Vives. 2025-05-09. Beyond the Standard Model contributions to dipole moments. https://arxiv.org/abs/2505.06345

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