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arXiv · 1907.12478

Loop-enhanced rate of neutrinoless double beta decay

Werner Rodejohann·Xun-Jie Xu
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Abstract

Neutrino masses can be generated radiatively. In such scenarios their masses are calculated by evaluating a self-energy diagram with vanishing external momentum, i.e. taking only the leading order term in a momentum expansion. The difference between the full self-energy and the mass is experimentally difficult to access, since one needs off-shell neurinos to observe them. However, massive Majorana neutrinos that mediate neutrinoless double beta decay ($0\nu\beta\beta$) are off-shell, with the virtuality of order 100 MeV. If the energy scale of the self-energy loop is of the order of this virtuality, the amplitude of double beta decay can be modified by the unsuppressed loop effect. This can have a drastic impact on the interpretation of future observations of the $0\nu\beta\beta$ decay.

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Werner Rodejohann, Xun-Jie Xu. 2019-07-29. Loop-enhanced rate of neutrinoless double beta decay. https://doi.org/10.1007/jhep11(2019)029

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