Speaker
Description
We will discuss possibilities of how to experimentally distinguish different mechanisms of $0\nu\beta\beta$-decay and thereby identify potential non-standard contributions. The different mechanisms possibly contributing to $0\nu\beta\beta$-decay are classified following an effective field theory approach. We find that when utilizing measurements of the leptonic phase space, i.e., the spectra and angular correlation of the outgoing electrons as well as measurements of the half-life in multiple isotopes one can sort the 32 different low-energy effective operators into multiple groups that in principle can result in different experimental signatures. Based on nuclear matrix elements from IBM2 we determine the required theoretical precision of the nuclear part of the $0\nu\beta\beta$-decay rate calculation that would be necessary to identify non-standard mechanisms via half-life measurements in multiple isotopes. Besides the uncertainties involved in the calculation of nuclear matrix elements, we find that the currently unknown low-energy constants that parameterize couplings in the chiral effective field theory are a limiting factor. Finally, we will present a Python tool developed alongside this work that can be used to study different models of $0\nu\beta\beta$. We are working towards making this tool publicly available in the near future.
