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R Martinez  F Ochoa 《Pramana》2012,79(4):883-886
A 3-3-1 model is constructed for three families that can be embedded into a single SU(8) unified model. Assuming appropriate branching rules and symmetry-breaking pattern, a complete fermion content is found within irreducible representations of SU(8), where light Standard Model fermions, heavy 3-3-1 fermions and superheavy fermions may be distinguished.  相似文献   

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作者索引     
《发光学报》2006,27(3):430-432
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《发光学报》2007,28(5):460-462
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Some 3-3-1 models predict the existence of a non-perturbative regime at the TeV scale. We study in these models and their supersymmetric extensions, the energy at which the non-perturbative limit and a Landau-like pole arise. An order of magnitude for the mass of the extra neutral vector boson, , present in these models is also obtained.Received: 12 October 2004, Revised: 1 November 2004, Published online: 21 December 2004PACS: 12.60.Cn, 12.60.Jv  相似文献   

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We construct the supersymmetric economical 3-3-1 model which contains inflationary scenario and avoids the monopole puzzle. Based on the spontaneous symmetry breaking pattern (with three steps), the F-term inflation is derived. The slow-roll parameters and η are calculated. By imposing as experimental five-year WMAP data on the spectral index n, we have derived a constraint on the number of e-folding N Q to be in the range from 25 to 50. The scenario for large-scale structure formation implied by the model is a mixed scenario for inflation and cosmic string, and the contribution to the CMBR temperature anisotropy depends on the ratio M X /M Pl. From the COBE data, we have obtained the constraint on the M X to be M X ∈ [1.22 × 1016, 0.98 × 1017] GeV. The upper value M X ≃ 1017 GeV is a result of the analysis in which the inflationary contribution to the temperature fluctuations measured by the COBE is 90%. The coupling α varies in the range: 10−7−10−1. This value is not so small, and it is a common characteristics of the supersymmetric unified models with the inflationary scenario. The spectral index n is a little bit smaller than 0.98. The SUGRA corrections are slightly different from the previous consideration. When ξ ≪ 1 and α lies in the above range, the spectral index gets the value consistent with the experimental five-year WMAP data. Comparing with string theory, one gets ξ < 10−8. Numerical analysis shows that α ≈ 10−6. To get inflation contribution to the CMBR temperature anisotropy ≈90%, the mass scale M X < 3.5 × 1014 GeV.  相似文献   

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The SU(3) C ⊗ SU(3) L ⊗ U(1) X gauge model with two Higgs triplets (the economical 3-3-1 model) is presented. The minimal Higgs potential is considered in detail, and new Higgs bosons with the mass proportional to the bilepton mass are predicted. In the effective approximation, the charged Higgs bosons H 2 ± are scalar bileptons, while the neutral scalar bosons H 0 and H 1 0 do not carry a lepton number. The couplings of the charged Higgs bosons to leptons and quarks are given. We show that Yukawa couplings of H 2 ± to ordinary leptons and quarks are lepton-number violating. The pair production of H 2 ± at high-energy e + e colliders with the polarization of the e +, e beams is studied in detail. A numerical evaluation shows that, if the Higgs mass is not too heavy, then the reaction can give an observable cross section in future colliders at a high degree of polarization. The reaction e + e H 2 ± W is also examined. We show that the production cross sections of H 2 ± W are very small, much below the pair production of H 2 ± , and, therefore, the associated production of H 2 ± and W is, in general, not expected to lead to easily observable signals in the e + e annihilation. The text was submitted by the authors in English.  相似文献   

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Possibleμ + sites have been identified by a comparison of measured spontaneous internal fields in YBa2Cu3O6+δ and REBa2Cu3O7−δ and of measured second moments and width of transverse field powder spectra with the corresponding calculated quantities. In the YBa2Cu3O7 system only one possibleμ + site emerges at a distance of ∼1.05 A from a chain oxygen O(4) at the position (0.15(1), 0.44(1), 0.071(1)). In the system YBa2Cu3O6 the only possibleμ + sites are near to an oxygen O(1) with z/c=0.133 and the same distance as above. The analysis leads also to improved valuesμ Ho = 2.2(1)μ B andμ Cu = 0.67(4)μ B and to a determination of the latters direction:μ Cu ‖〈110〉.  相似文献   

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In the framework of a 3-3-1 model with right-handed neutrinos and three scalar triplets we consider different spontaneous symmetry breaking patterns seeking for a non-linear realization of accidental symmetries of the model, which will produce physical Nambu–Goldstone (NG) bosons in the neutral scalar spectrum. We make a detailed study of the safety of the model concerning the NG boson emission in energy-loss processes which could affect the standard evolution of astrophysical objects. We consider the model with a \(\mathbb {Z}_2\) symmetry, conventionally used in the literature, finding that in all of the symmetry breaking patterns the model is excluded. Additionally, looking for solutions for that problem, we introduce soft \(\mathbb {Z}_2\)-breaking terms in the scalar potential in order to remove the extra accidental symmetries and at the same time maintain the model as simple as possible. We find that there is only one soft \(\mathbb {Z}_2\)-breaking term that enables us to get rid of the problematic NG bosons.  相似文献   

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Das Phanomen der Lyolumineszenz wurde erstmuls 1895 von Wiedemann und Schmidt an Alkalihalogeniden nach Bestrahlung mit Katodenstrahlcn beobachtet. In ihrer Arbeit “Uber Luminescenz", die in den ”Annalen der Physik und Chemie" erschien, schreiben sie [24]:

“Ferner haben wir eine weitero Art der Luminescenz aufgefunden, welche man mit dem Namen Lyoluininescenz belegen konnto. In gewissen Fallen tritt beim Losen von Substanzen eine Lichtentwicklung auf, nnchdem sie vorher bestrablt worden sind, wahrend sie eine solche ohne Bestrahlung nicht zeigen“.  相似文献   

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