2,704 research outputs found

    Explicit SO(10) Supersymmetric Grand Unified Model for the Higgs and Yukawa Sectors

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    A complete set of fermion and Higgs superfields is introduced with well-defined SO(10) properties and U(1) x Z_2 x Z_2 family charges from which the Higgs and Yukawa superpotentials are constructed. The structures derived for the four Dirac fermion and right-handed Majorana neutrino mass matrices coincide with those previously obtained from an effective operator approach. Ten mass matrix input parameters accurately yield the twenty masses and mixings of the quarks and leptons with the bimaximal atmospheric and solar neutrino vacuum solutions favored in this simplest version.Comment: Published version appearing in PRL in which small modifications to original submission and a paragraph concerning proton decay appea

    Leptogenesis in the type III seesaw mechanism

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    It is shown that the type III seesaw mechanism proposed recently can have certain advantages over the conventional (or type I) seesaw mechanism for leptogenesis. In particular a resonant enhancement of leptogenesis via heavy quasi-Dirac right-handed neutrino pairs can occur without a special flavor form or "texture" of the mass matrices being assumed. Some of the requirements for neutrino mixing and leptogenesis are effectively decoupled.Comment: 12 pages including one figure, several references adde

    Lepton Flavor Violation in Supersymmetric SO(10) Grand Unified Models

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    The study for lepton flavor violation combined with the neutrino oscillation may provide more information about the lepton flavor structure of the grand unified theory. In this paper, we study two lepton flavor violation processes, τμγ\tau\to \mu\gamma and ZτμZ\to \tau\mu, in the context of supersymmetric SO(10) grand unified models. We find the two processes are both of phenomenological interest. In particular the latter may be important in some supersymmetric parameter space where the former is suppressed. Thus, Z-dacay may offer another chance for looking for lepton flavor violation.Comment: 26 pages, 10 figure

    Texture of fermion mass matrices in partially unified theories

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    We investigate the texture of fermion mass matrices in theories with partial unification (for example SU(2)L×SU(2)R×SU(4)c SU(2)_L\times SU(2)_R\times SU(4)_c) at a scale 1012\sim 10^{12} GeV. Starting with the low energy values of the masses and the mixing angles, we find only two viable textures with atmost four texture zeros. One of these corresponds to a somewhat modified Fritzsch textures. A theoretical derivataion of these textures leads to new interesting relations among the masses and the mixing angles.Comment: 10 pages(Latex

    Prognostic Value of Diagnostic Sonography in Patients With Plantar Fasciitis

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135343/1/jum201534101729.pd

    Large Angle MSW Solution in Grand Unified Theories with SU(3) X U(1) Horizontal Symmetry

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    We construct a model with a SU(3) X U(1) horizontal symmetry in the context of Grand Unified Theories. In our models, the bi-maximal lepton mixing and suitable neutrino masses for the large angle MSW solution are obtained without any fine-tuning due to the spontaneously broken SU(3)_H symmetry. The three generations of quarks and leptons are unified as members of the SU(3)_H fundamental representation, and the U(1)_H charge gives the origin of the fermion mass hierarchy and mixing angles. We present two explicit examples of SU(5)_GUT and SO(10)_GUT models, in which the Yukawa structures are given successfully.Comment: 23 pages, 6 figures, references adde

    Leptonic CP violation: zero, maximal or between the two extremes

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    Discovery of the CP-violation in the lepton sector is one of the challenges of the particle physics. We search for possible principles, symmetries and phenomenological relations that can lead to particular values of the CP-violating Dirac phase, δ\delta. In this connection we discuss two extreme cases: the zero phase, δ=0\delta = 0, and the maximal CP-violation, δ=±π/2\delta = \pm \pi/2, and relate them to the peculiar pattern of the neutrino mixing. The maximal CP-violation can be related to the νμντ\nu_\mu - \nu_\tau reflection symmetry. We study various aspects of this symmetry and introduce a generalized reflection symmetry that can lead to an arbitrary phase that depends on the parameter of the symmetry transformation. The generalized reflection symmetry predicts a simple relation between the Dirac and Majorana phases. We also consider the possibility of certain relations between the CP-violating phases in the quark and lepton sectors.Comment: 34 pages, no figures; v3: version appeared in JHE

    Unique Mass Texture for Quarks and Leptons

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    Texture specific quark mass matrices which are hermitian and hierarchical are examined in detail . In the case of texture 6 zeros matrices, out of sixteen possibilities examined by us, none is able to fit the low energy data (LED), for example, Vus=0.2196±0.0023V_{us} = 0.2196 \pm 0.0023, Vcb=0.0395±0.0017V_{cb} = 0.0395 \pm 0.0017, VubVcb=0.08±0.02\frac{V_{ub}}{V_{cb}} = 0.08 \pm 0.02, VtdV_{td} lies in the range 0.0040.0130.004 - 0.013 (PDG). Similarly none of the 32 texture 5 zeros mass matrices considered is able to reproduce LED. In particular, the latest data from LEP regarding Vub/Vcb(=0.093±0.016)|V_{ub}|/|V_{cb}|(=0.093\pm0.016) rules out all of them. In the texture 4 zeros case, we find that there is a unique texture structure for UU and DD mass matrices which is able to fit the data.Comment: 12 pages, LaTeX,some changes in the references,minor changes in the text,to appear in Phys Rev D(Rapid communications

    Top quark electric and chromo electric dipole moments in the general two Higgs Doublet model

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    We study the electric and chromo electric dipole moment of top quark in the general two Higgs Doublet model (model III). We analyse the dependency of this quantity to the new phases coming from the complex Yukawa couplings and masses of charged and neutral Higgs bosons. We observe that the electric and chromo elecric dipole moments of top quark are at the order of 10^{-21} e cm and 10^{-20} g_s cm, which are extremely large values compared to ones calculated in the SM and also two Higgs Doublet model with real Yukawa couplings.Comment: 9 pages,10 figure
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