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arXiv · 1711.06181

Can one ever prove that neutrinos are Dirac particles?

Martin Hirsch·Rahul Srivastava·José W. F. Valle
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Abstract

According to the "Black Box" theorem the experimental confirmation of neutrinoless double beta decay ($0 \nu 2 \beta$) would imply that at least one of the neutrinos is a Majorana particle. However, a null $0 \nu 2 \beta$ signal cannot decide the nature of neutrinos, as it can be suppressed even for Majorana neutrinos. In this letter we argue that if the null $0 \nu 2 \beta$ decay signal is accompanied by a $0 \nu 4 \beta$ quadruple beta decay signal, then at least one neutrino should be a Dirac particle. This argument holds irrespective of the underlying processes leading to such decays.

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Martin Hirsch, Rahul Srivastava, José W. F. Valle. 2017-11-16. Can one ever prove that neutrinos are Dirac particles?. https://doi.org/10.1016/j.physletb.2018.03.073

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