Neutrino masses in effective rank-5 subgroups of E{sub 6}. I. Nonsupersymmetric case
- Department of Physics, Concordia University, 7141 Sherbrooke Street West, Montreal, Quebec, H4B 1R6 (Canada)
- Particle Theory Group, Department of Physics, College of William and Mary, Williamsburg, Virginia 23187-8795 (United States)
The neutral fermion sectors of E{sub 6}-inspired low-energy models, in particular, the alternative left-right and inert models, are considered in detail within the nonsupersymmetric scenario. We show that in their simplest form, these models always predict, for each generation, the lightest neutrino to be a SU(2){sub L} singlet, as well as two extra neutrinos with masses of the order of the up-quark mass. In order to recover standard model phenomenology, additional assumptions in the form of discrete symmetries and/or new interactions are needed. These are classified as the discrete symmetry, higher-dimensional operators, and additional neutral fermion methods. The discrete symmetry method can solve the problem, but requires additional Higgs doublets that do not get vacuum expectation values. The higher-dimensional operators method predicts no sterile neutrino, and that the active neutrinos mix with a heavy isodoublet neutrino, thus slightly suppressing the couplings of active neutrinos, with interesting phenomenological implications. The additional neutral fermion method also predicts this suppression, and also naturally includes one or more sterile neutrinos. This scenario allows the existence of sterile neutrino(s) in either a 3+1 or 2+2 structure at low energies, which are favored by the Los Alamos Liquid Scintillation Neutrino Detector result.
- OSTI ID:
- 20709432
- Journal Information:
- Physical Review. D, Particles Fields, Vol. 71, Issue 11; Other Information: DOI: 10.1103/PhysRevD.71.113001; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
- Country of Publication:
- United States
- Language:
- English
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