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arXiv · 2504.00081

Importance of Loop Effects in Probing Lepton Number Violation

Lukáš Gráf·Chandan Hati·Ana Martín-Galán·Oliver Scholer
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Abstract

The discovery of the lepton number violation would be a smoking gun signal for physics beyond the Standard Model, and its most sensitive probe is the search for neutrinoless double beta decay ($0\nu\beta\beta$). Working in the framework of the Standard Model Effective Field Theory (SMEFT), we show that one-loop effects can remarkably improve the tree-level bounds on the new-physics scales for several dimension-7 operators. Using ultraviolet model examples, we then showcase the competition among $0\nu\beta\beta$ contributions induced by dimension-7 and loop-level dimension-5 SMEFT operators.

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Lukáš Gráf, Chandan Hati, Ana Martín-Galán, Oliver Scholer. 2025-03-31. Importance of Loop Effects in Probing Lepton Number Violation. https://arxiv.org/abs/2504.00081

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