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arXiv · 1801.04496

Shell model study on the possibility of using an effective field theory for disentangling several contributions to the neutrinoless double-beta decay

Andrei Neacsu·Mihai Horoi
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Abstract

Neutrinoless double-beta decay represents the most promising approach for revealing some of the most important, yet-unknown, properties of neutrinos related to their absolute masses and their nature. This transition involves beyond standard model theories that predict the violation of the lepton number conservation by two units. There is no experimental confirmation yet for this decay, but new experiments have set lower-limits for the associated half-lives in the case of several isotopes. Using an effective field theory that describes this transition, we calculate half-life ratios for five experimentally interesting isotopes in the case of 12 lepton number violating couplings. These half-life ratios can be used to probe the sensitivity of the five isotopes in relation to their respective mechanisms, to predict the half-life limits needed to match the different experimental results, and in the case of experimental confirmation, these ratios could possibly indicate the dominant mechanism of the transition. We provide an analysis that could reveal valuable information regarding the dominant neutrinoless double-beta decay mechanism, if experimental half-life data becomes available for different isotopes.

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Andrei Neacsu, Mihai Horoi. 2018-01-14. Shell model study on the possibility of using an effective field theory for disentangling several contributions to the neutrinoless double-beta decay. https://doi.org/10.1103/physrevc.98.035502

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