Majorana neutrino transition magnetic moments in left-right symmetric models

Abstract

Transition magnetic moments of Majorana neutrinos are discussed in the frame of the most natural version of the LR model (with left- and right-handed triplets and a bidoublet in the Higgs sector). We show that their largest values could be at most $6\cdot 10^{-13} μ_B$ from diagrams with $W_L$ in the loop. This could happen for specific models where (i) neutrino-charged lepton mixing is maximal and (ii) $κ_1 \simeq κ_2$ (VEVs for neutral Higgs fields in the bidoublet $ϕ$ are equal). Contributions from diagrams with charged Higgses in the loop are smaller than those in the SM with right-handed neutrinos.