Neutrino Masses from Loop-Induced Dirac Yukawa Couplings
Abstract
We consider a possibility to naturally explain tiny neutrino masses without the lepton number violation. We study a simple model with SU(2)_L singlet charged scalars (s_1^+, s_2^+) as well as singlet right-handed neutrino (nu_R). Yukawa interactions for Dirac neutrinos, which are forbidden at the tree level by a softly-broken Z_2 symmetry, are induced at the one-loop level via the soft-breaking term in the scalar potential. Consequently neutrinos obtain small Dirac masses after the electroweak symmetry breaking. It is found that constrains from neutrino oscillation measurements and lepton flavor violation search results (especially for mu to e gamma) can be satisfied. We study the decay pattern of the singlet charged scalars, which could be tested at the LHC and the ILC. We discuss possible extensions also, e.g. to introduce dark matter candidate.
Keywords
Cite
@article{arxiv.1106.2480,
title = {Neutrino Masses from Loop-Induced Dirac Yukawa Couplings},
author = {Shinya Kanemura and Takehiro Nabeshima and Hiroaki Sugiyama},
journal= {arXiv preprint arXiv:1106.2480},
year = {2011}
}
Comments
14 pages, 1 figure