New Leptoquark Mechanism of Neutrinoless Double Beta Decay

Abstract

A new mechanism for neutrinoless double beta ($\text{znbb}$) decay based on leptoquark exchange is discussed. Due to the specific helicity structure of the effective four-fermion interaction this contribution is strongly enhanced compared to the well-known mass mechanism of $\text{znbb}$ decay. As a result the corresponding leptoquark parameters are severely constrained from non-observation of $\text{znbb}$-decay. These constraints are more stringent than those derived from other experiments.

Comments: LaTeX, 6 pages, 1 figure