Scalarful double beta decay

TL;DR

This paper analyzes scalar emissions in double beta decay, exploring their spectral signatures and sensitivities in experiments, considering various scalar types and couplings within an effective field theory framework.

Contribution

It provides a comprehensive effective field theory analysis of scalar emissions in double beta decay, including massive scalars and exotic couplings, updating previous models.

Findings

Spectral shapes are sensitive to scalar properties.

Double beta decay experiments can probe scalar couplings.

Extended analysis to sterile neutrino interactions.

Abstract

We revisit scalar emissions in double beta decays of nuclei, often discussed in the context of Majoron models, in light of the latest developments on the study of neutrinoless double beta decay amplitudes from an effective field theory approach. The sensitivity of double beta decay experiments to this process is assessed through an analysis of spectral shapes, and the study is extended to massive scalars, scalars coupling to sterile neutrinos, and exotic right-handed effective couplings.