https://doi.org/10.1140/epjc/s10052-024-13262-y
Regular Article - Theoretical Physics
Searching for signatures of new physics in 
to distinguish between Dirac and Majorana neutrinos
1
Department of Physics and IPAP, Yonsei University, 03722, Seoul, Korea
2
Faculty of Physics, Institute of Theoretical Physics, University of Warsaw, ul. Pasteura 5, 02-093, Warsaw, Poland
3
Universidad Técnica Federico Santa María, Casilla 110-V, Valparaiso, Chile
Received:
4
June
2024
Accepted:
16
August
2024
Published online:
2
September
2024
We conduct a model-independent analysis of the distinct signatures of various generic new physics possibilities in the decay 
by analyzing the branching ratio as well as the missing mass-square distribution. Considering the final neutrinos to be of the same flavor with non-zero mass, we discuss the new physics contributions for both Dirac and Majorana neutrino possibilities. In our study, we utilize the analytical relations among form factors in semi-leptonic 
transitions, which are consistent with current lattice QCD predictions to a very high numerical accuracy. We provide constraints on different new physics parameters, taking into account the recent measurement of 
branching ratio by the Belle-II collaboration. In future, if the missing mass-square distribution for decay gets reported by Belle-II with analysis of more events than their present data set, one can not only investigate possible new physics effects in these decays, but also probe the Dirac/Majorana nature of the neutrinos using quantum statistics, since a difference between the two cases is known to exist in the presence of non-standard neutrino interactions.
© The Author(s) 2024
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Funded by SCOAP3.
