Flavor of product-group grand unified theories
- Physics Department, Technion-Israel Institute of Technology, Haifa 32000 (Israel)
The doublet-triplet splitting problem can be simply solved in product-group GUT models, using a global symmetry that distinguishes the doublets from the triplets. Apart from giving the required mass hierarchy, this 'triplet symmetry' can also forbid some of the triplet couplings to matter. We point out that, since this symmetry is typically generation-dependent, it gives rise to nontrivial flavor structure. Furthermore, because flavor symmetries cannot be exact, the triplet-matter couplings are not forbidden then but only suppressed. We construct models in which the triplet symmetry gives acceptable proton decay rate and fermion masses. In some of the models, the prediction m{sub b}{approx}m{sub {tau}} is retained, while the similar relation for the first generation is corrected. Finally, all this can be accomplished with triplets somewhat below the GUT scale, supplying the right correction for the standard model gauge couplings to unify precisely.
- OSTI ID:
- 20774835
- Journal Information:
- Physical Review. D, Particles Fields, Vol. 73, Issue 11; Other Information: DOI: 10.1103/PhysRevD.73.115008; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
- Country of Publication:
- United States
- Language:
- English
Similar Records
Low intermediate scales for leptogenesis in supersymmetric SO(10) grand unified theories
A Domino Theory of Flavor