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Bordes, J., Hong-Mo, C., & Tsun, T. S. (2018). The Z boson in the framed standard model. Int. J. Mod. Phys. A, 33(32), 1850190–19pp.
Abstract: The framed standard model (FSM), constructed initially for explaining the existence of three fermion generations and the hierarchical mass and mixing patterns of quarks and leptons,(1,2) suggests also a “hidden sector” of particles(3) including some dark matter candidates. It predicts in addition a new vector boson G, with mass of order TeV, which mixes with the gamma and Z of the standard model yielding deviations from the standard mixing scheme, all calculable in terms of a single unknown parameter mG. Given that standard mixing has been tested already to great accuracy by experiment, this could lead to contradictions, but it is shown here that for the three crucial and testable cases so far studied (i) m(Z) – m(W), (ii) Gamma(Z -> l(+)l(-)), (iii) Gamma(Z -> hadrons), the deviations are all within the present stringent experimental bounds provided m(G) > 1 TeV, but should soon be detectable if experimental accuracy improves. This comes about because of some subtle cancellations, which might have a deeper reason that is not yet understood. By virtue of mixing, G can be produced at the LHC and appear as a l(+)l(-) anomaly. If found, it will be of interest not only for its own sake but serve also as a window on to the “hidden sector” into which it will mostly decay, with dark matter candidates as most likely products.
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Bordes, J., Chan, H. M., & Tsun, S. S. (2018). A closer study of the framed standard model yielding testable new physics plus a hidden sector with dark matter candidates. Int. J. Mod. Phys. A, 33(33), 1850195–75pp.
Abstract: This closer study of the FSM (1) retains the earlier results of Ref. 1 in offering explanation for the existence of three fermion generations, as well as the hierarchical mass and mixing patterns of leptons and quarks; (II) predicts a vector boson G with mass of order TeV which mixes gamma with and Z of the standard model. The subsequent deviations from the standard mixing scheme are calculable in terms of the G mass. While these deviations for (i) mz – mw, (ii) Gamma(Z -> l (+)l( -)), and (iii) F(Z -> hadrons) are all within present experimental errors so long as mG > 1 TeV, they should soon be detectable if the G mass is not too much bigger; (III) suggests that in parallel to the standard sector familiar to us, there is another where the roles of flavour and colour are interchanged. Though quite as copiously populated and as vibrant in self-interactions as our own, it communicates but little with the standard sector except via mixing through a couple of known portals, one of which is the gamma – Z – G complex noted in (II), and the other is a scalar complex which includes the standard model Higgs. As a result, the new sectors paper. appears hidden to us as we appear hidden to them, and so its lowest members with masses of order 10 MeV, being electrically neutral and seemingly stable, but abundant, may make eligible candidates as constituents of dark matter. A more detailed summary of these results together with some remarks on the model's special theoretical features can be found in the last section of this paper.
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Centelles Chulia, S., & Trautner, A. (2020). Asymmetric tri-bi-maximal mixing and residual symmetries. Mod. Phys. Lett. A, 35(35), 2050292–15pp.
Abstract: Asymmetric tri-bi-maximal mixing is a recently proposed, grand unified theory (GUT) based, flavor mixing scheme. In it, the charged lepton mixing is fixed by the GUT connection to down-type quarks and a T-13 flavor symmetry, while neutrino mixing is assumed to be tri-bi-maximal (TBM) with one additional free phase. Here we show that this additional free phase can be fixed by the residual flavor and CP symmetries of the effective neutrino mass matrix. We discuss how those residual symmetries can be unified with T-13 and identify the smallest possible unified flavor symmetries, namely (Z(13)xZ(13))(sic)D-12 and (Z(13)xZ(13))(sic)S-4. Sharp predictions are obtained for lepton mixing angles, CP violating phases and neutrinoless double beta decay.
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Meloni, D., Morisi, S., & Peinado, E. (2011). Neutrino phenomenology and stable dark matter with A(4). Phys. Lett. B, 697(4), 339–342.
Abstract: We present a model based on the A(4) non-Abelian discrete symmetry leading to a predictive five-parameter neutrino mass matrix and providing a stable dark matter candidate. We found an interesting correlation among the atmospheric and the reactor angles which predicts theta(23) similar to pi/4for very small reactor angle and deviation from maximal atmospheric mixing for large theta(13). Only normal neutrino mass spectrum is possible and the effective mass entering the neutrinoless double beta decay rate is constrained to be vertical bar m(ee)vertical bar > 4 x 10(-4) eV.
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Morisi, S., & Peinado, E. (2011). Admixture of quasi-Dirac and Majorana neutrinos with tri-bimaximal mixing. Phys. Lett. B, 701(4), 451–457.
Abstract: We propose a realization of the so-called bimodal/schizophrenic model proposed recently. We assume 54, the permutation group of four objects as flavor symmetry giving tri-bimaximal lepton mixing at leading order. In these models the second massive neutrino state is assumed quasi-Dirac and the remaining neutrinos are Majorana states. In the case of inverse mass hierarchy, the lower bound on the neutrinoless double beta decay parameter m(ee) is about two times that of the usual lower bound, within the range of sensitivity of the next generation of experiments.
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LHCb Collaboration(Aaij, R. et al), Henry, L., Jashal, B. K., Martinez-Vidal, F., Oyanguren, A., Remon Alepuz, C., et al. (2021). Search for the rare decay B-0 -> J/psi phi. Chin. Phys. C, 45(4), 043001–14pp.
Abstract: A search for the rare decay B-0 -> J/psi phi, is performed using pp collision data collected with the LHCb detector at centre-of-mass energies of 7, 8 and 13 TeV, corresponding to an integrated luminosity of 9 fb(-1). No significant signal of the decay is observed and an upper limit of 1.1 x 10(-7) at 90% confidence level is set on the branching fraction.
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Mathieu, V., & Vento, V. (2010). eta-eta ' mixing in the flavor basis and large N. Phys. Lett. B, 688(4-5), 314–318.
Abstract: The mass matrix for eta-eta' is derived in the flavor basis at O(p(4)) of the chiral Lagrangian using the large N approximation. Under certain assumptions, the mixing angle phi = 41.4 degrees and the decay constants ratio f(K)/f(pi) = 1.15 are calculated in agreement with the data. It appears that the FKS scheme arises as a special limit of the chiral Lagrangian. Their mass matrix is obtained without the hypothesis on the mixing pattern of the decay constants.
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Tortola, M. (2013). Status of three-neutrino oscillation parameters. Fortschritte Phys.-Prog. Phys., 61(4-5), 427–440.
Abstract: Here we review the current status of global fits to neutrino oscillation data within the three-flavour framework. In our analysis we include the most recent data from solar and atmospheric neutrino experiments as well as the latest results from the long-baseline accelerator neutrino experiments and the recent measurements of reactor neutrino disappearance reported by Double Chooz, Daya Bay and RENO. We present updated determinations for the two neutrino mass splittings and the three mixing angles responsible for neutrino oscillations that, for the first time, have all been measured with 1 sigma accuracies ranging from 3 to 15%. A weak sensitivity for the CP violating phase is also reported from the global analysis.
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Morisi, S., & Valle, J. W. F. (2013). Neutrino masses and mixing: a flavour symmetry roadmap. Fortschritte Phys.-Prog. Phys., 61(4-5), 466–492.
Abstract: Over the last ten years tri-bimaximal mixing has played an important role in modeling the flavour problem. We give a short review of the status of flavour symmetry models of neutrino mixing. We concentrate on non-Abelian discrete symmetries, which provide a simple way to account for the TBM pattern. We discuss phenomenological implications such as neutrinoless double beta decay, lepton flavour violation as well as theoretical aspects such as the possibility to explain quarks and leptons within a common framework, such as grand unified models.
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Rinaldi, M., & Vento, V. (2020). Pure glueball states in a light-front holographic approach. J. Phys. G, 47(5), 055104–12pp.
Abstract: A phenomenological analysis of the scalar glueball and scalar meson spectra is carried out by using the AdS/QCD framework in the bottom-up approach. The resulting spectra are in good agreement for glueballs with lattice QCD results and for mesons with PDG data. We make use of the relation between the mode functions in AdS/QCD and the wave functions in Light-Front QCD to discuss the mixing of glueballs and mesons. The results of our investigation point out that above 2 GeV scalar particles will appear in almost degenerate pairs of unmixed glueball and mesons states leading to an interesting phenomenology whereby gluon dynamics could be well investigated.
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