$\Delta$L=2 hyperon decays induced by Majorana neutrinos and doubly-charged scalars

Autor: Hernández-Tomé, G., Castro, G. López, Portillo-Sánchez, D.
Rok vydání: 2021
Předmět:
Druh dokumentu: Working Paper
DOI: 10.1103/PhysRevD.105.113001
Popis: Searches for $\Delta L=2$ decays are crucial to disentangle the Dirac vs Majorana nature of neutrinos. While neutrinoless nuclear double beta decays are the most promising tool to look for di-electron signals of $\Delta L=2$, searches of di-lepton channels with other flavors are far less limited by statistics. We revisit the calculation of $\Delta L=2$ decays of hyperons $B^-_i\to B^+_f\ell^-\ell'^-$. We compute the rates of these decays by including the hyperon form factors, which yields finite results in the one-loop model mechanism involving Majorana neutrinos (long-range contributions). In addition, we study the short-range contributions to these kinds of processes in two appealing scenarios. First, we consider the effects of heavy Majorana neutrinos in low-scale seesaw models that involve a minimal parametrization with only two heavy Majorana states. Second, we study an alternative model where $\Delta L=2$ decays are induced by a scalar boson coupled to di-leptons to provide additional predictions.
Comment: 13 pages and 3 figures; clarification and discussion added, typos corrected, version accepted for publication in PRD
Databáze: arXiv