5,062 research outputs found

    M\"{o}ller and Bhabha scattering in the noncommutative standard model

    Full text link
    We study the M\"{o}ller and Bhabha scattering in the noncommutative extension of the standard model(SM) using the Seiberg-Witten maps of this to first order of the noncommutative parameter θμν\theta_{\mu \nu}. We look at the angular distribution dσ/dΩd\sigma/d\Omega to explore the noncommutativity of space-time at around ΛNC\Lambda_{NC} \sim TeV and find that the distribution deviates significantly from the one obtained from the commutative version of the standard model.Comment: 15 pages, 14 eps figures.Text is modified a little and version to appear in Phys.Rev.

    Constraints on the phase γ\gamma and new physics from BKπB\to K\pi Decays

    Full text link
    Recent results from CLEO on BKπB\to K\pi indicate that the phase γ\gamma may be substantially different from that obtained from other fit to the KM matrix elements in the Standard Model. We show that γ\gamma extracted using BKπ,ππB\to K\pi, \pi\pi is sensitive to new physics occurring at loop level. It provides a powerful method to probe new physics in electroweak penguin interactions. Using effects due to anomalous gauge couplings as an example, we show that within the allowed ranges for these couplings information about γ\gamma obtained from BKπ,ππB\to K \pi, \pi\pi can be very different from the Standard Model prediction.Comment: Revised version with analysis done using new data from CLEO. RevTex, 11 Pages with two figure

    Left-Right Symmetry and Supersymmetric Unification

    Get PDF
    The existence of an SU(3) X SU(2)_L X SU(2)_R X U(1) gauge symmetry with g_L = g_R at the TeV energy scale is shown to be consistent with supersymmetric SO(10) grand unification at around 1O^{16} GeV if certain new particles are assumed. The additional imposition of a discrete Z_2 symmetry leads to a generalized definition of R parity as well as highly suppressed Majorana neutrino masses. Another model based on SO(10) X SO(10) is also discussed.Comment: 11 pages, 2 figures not included, UCRHEP-T124, Apr 199

    The Optical Energy Gap in MO0.5 W0.5Se2 Single Crystals Grown by a Direct Vapour Transport Technique

    Get PDF

    CP-Violation For BXsl+lB \to X_sl^+l^- Including Long-Distance Effects

    Full text link
    We consider the CP violating effect for BXsl+lB\to X_sl^+l^- process, including both short and long distance effects. We obtain the CP asymmetry parameter and present its variation over the dilepton mass.Comment: 9 pages, Latex file, one figure include

    A Critical Study of B Decays to Light Pseudoscalar

    Get PDF
    Motivated by the large branching ratios observed for the process BηKB\to\eta^{\prime}K, we examine critically all the ingredients that go into estimates of B decays into two light pseudoscalars. Within factorization approximation, we examine several assumptions on the input parameters that could have a strong bearing on the predictions. Among these are (i) the QCD scale μ\mu (ii) value of the form factors (iii) value of the light quark masses, and in particular msm_s (iv) the value ξ=1/Nc\xi=1/N_c, (v) charm content of η\eta^{\prime}. It is possible to account for all the data without invoking new physics, though future experiments will provide tighter constraints on the parameter space. We fin that CP violating asymmetries are in the observable range for some modes.Comment: 29 pages(Latex), 17 figures, a few changes have been made, version to appear in Phys.Rev.

    Texture of fermion mass matrices in partially unified theories

    Get PDF
    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
    corecore