18,858 research outputs found

    The T7 flavor symmetry in 3-3-1 model with neutral leptons

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    We construct a 3-3-1 model based on non-Abelian discrete symmetry T7T_7 responsible for the fermion masses. Neutrinos get masses from only anti-sextets which are in triplets 3‾\underline{3} and 3‾∗\underline{3}^* under T7T_7. The flavor mixing patterns and mass splitting are obtained without perturbation. The tribimaximal form obtained with the breaking T7→Z3T_7 \rightarrow Z_3 in charged lepton sector and both T7→Z3T_7 \rightarrow Z_3 and Z3→{Identity}Z_3 \rightarrow \{\mathrm{Identity}\} must be taken place in neutrino sector but only apart in breakings Z3→{Identity}Z_3 \rightarrow \{\mathrm{Identity}\} (without contribution of \si'), and the upper bound on neutrino mass ∑i=13mi\sum_{i=1}^3m_i at the level is presented. The Dirac CP violation phase δ\delta is predicted to either π2\frac{\pi}{2} or 3π2\frac{3\pi}{2} which is maximal CP violation. From the Dirac CP violation phase we obtain the relation between Euler's angles which is consistent with the experimental in PDG 2012. On the other hand, the realistic lepton mixing can be obtained if both the direction for breakings T7→Z3T_7 \rightarrow Z_3 and Z3→{Identity}Z_3 \rightarrow \{\mathrm{Identity}\} are taken place in neutrino sectors. The CKM matrix is the identity matrix at the tree-level.Comment: 39 pages, 16 figures. arXiv admin note: substantial text overlap with arXiv:1312.5034; and text overlap with arXiv:1304.0921, arXiv:1306.4138, arXiv:1311.6729, arXiv:1310.4614 by other author

    A 3-3-1 model with right-handed neutrinos based on the Δ(27)\Delta\left(27\right) family symmetry

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    We present the first multiscalar singlet extension of the 3-3-1 model with right-handed neutrinos, based on the Δ(27)\Delta \left( 27\right) family symmetry, supplemented by the Z4⊗Z8⊗Z14Z_{4}\otimes Z_{8}\otimes Z_{14} flavor group, consistent with current low energy fermion flavor data. In the model under consideration, the light active neutrino masses are generated from a double seesaw mechanism and the observed pattern of charged fermion masses and quark mixing angles is caused by the breaking of the Δ(27)⊗Z4⊗Z8⊗Z14\Delta \left( 27\right) \otimes Z_{4}\otimes Z_{8}\otimes Z_{14} discrete group at very high energy. Our model has only 14 effective free parameters, which are fitted to reproduce the experimental values of the 18 physical observables in the quark and lepton sectors. The obtained physical observables for the quark sector agree with their experimental values, whereas those ones for the lepton sector also do, only for the inverted neutrino mass hierarchy. The normal neutrino mass hierarchy scenario of the model is disfavored by the neutrino oscillation experimental data. We find an effective Majorana neutrino mass parameter of neutrinoless double beta decay of mββ=m_{\beta \beta }= 22 meV, a leptonic Dirac CP violating phase of 34∘34^{\circ } and a Jarlskog invariant of about 10−210^{-2} for the inverted neutrino mass spectrum.Comment: 22 pages. Final version published in European Physical Journal C. arXiv admin note: text overlap with arXiv:1601.03300, arXiv:1309.656
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