Hyperon neutrinoless double beta decays in chiral perturbation theory

Abstract

We study the neutrinoless double beta decays of spin-1/2 hyperons, $B_1^{-}\to B_2^{+}{\ell }^{-}{\ell }^{-}$ with $B_1^{-}\in \{{\Sigma }^{-},{\Xi }^{-}\}$ and $B_2^{+}\in \{p,{\Sigma }^{+}\}$, which violate lepton number by two units. The decay amplitudes are computed within covariant baryon chiral perturbation theory at the one-loop level. Dalitz plots of the squared amplitude for six physical decay processes are presented in this proceeding, while a detailed numerical analysis will be presented in a forthcoming publication.

Comments: 4 pages, 3 figures, 2 tables, proceeding of The 29th International Nuclear Physics Conference (INPC 2025), Daejeon, Korea, 25-30 May, 2025