Constraining Sterile Neutrinos Using Decay Width Measurements of SM Bosons

Abstract

The mixing of right-handed neutrinos with the SM neutrinos contributes to the interactions of these neutrinos with the SM particles. Consequently, they will contribute to the decay widths of the SM W, Z, and Higgs bosons provided that they are kinematically allowed to be produced from these SM gauge bosons. Here, we show that the measured decay widths of Higgs, Z andW bosons can be used to probe sterile neutrinos, if they are kinematically allowed to be produced from these heavy Standard Model (SM) particle decays via the active-sterile neutrino mixing. We analyze the sensitivity of these measured SM quantities to constrain the active-sterile neutrino mixing as a function of the sterile neutrino mass. We make a comparative study of these constraints with other existing constraints from electroweak precision data, beam dump experiments, and peak searches, as well as from big bang nucleosynthesis.

Keywords

• left-right symmetric model, seesaw mechanism, sterile neutrino