158 research outputs found

    Phenomenology of CP Violation in a Flavor Blind MSSM and Beyond

    Full text link
    We present an analysis of low energy CP violating observables in the Minimal Supersymmetric Standard Model (MSSM). We focus on the predictions of CP violation in b -> s transitions in the framework of a flavor blind MSSM, where the CKM matrix remains the only source of flavor violation, but additional CP violating phases are introduced in the soft SUSY breaking sector. We find large and strongly correlated effects in Delta F = 0 observables like the electric dipole moments (EDMs) of the electron and the neutron, as well as in Delta F = 1 observables like the time dependent CP asymmetries in B -> phi K_s and B -> eta' K_s, the direct CP asymmetry in b -> s gamma and in several CP asymmetries in B -> K* mu+ mu-. On the other hand, observables that are only sensitive to CP violation in Delta F = 2 transitions, in particular the B_s mixing phase, are found to be SM like in this framework. We stress that only in presence of additional sources of flavor violation, sizeable New Physics effects to CP violation in meson mixing can occur.Comment: 4 pages, 1 figure, submitted to the proceedings of the 17th International Conference on Supersymmetry and the Unification of Fundamental Interactions (SUSY 09), Boston, MA, June 5-10, 200

    Searching for New Physics with Flavor Violating Observables

    Get PDF
    In this talk, I review the status and prospects of several low energy flavor observables that are highly sensitive to New Physics effects. In particular I discuss the implications for possible New Physics in b --> s transitions coming from the recent experimental results on the B_s mixing phase, the branching ratio of the rare decay B_s --> mu+mu-, and angular observables in the B --> K* mu+mu- decay. Also the recent evidence for direct CP violation in singly Cabibbo suppressed charm decays and its interpretation in the context of New Physics models is briefly discussed.Comment: 8 pages, 2 figures, contribution to the proceedings of "Les Rencontres de Physique de la Vallee d'Aoste", La Thuile, Italy, February 26 - March 3, 201

    New physics in b→sb\to s transitions after LHC run 1

    Full text link
    We present results of global fits of all relevant experimental data on rare b→sb \to s decays. We observe significant tensions between the Standard Model predictions and the data. After critically reviewing the possible sources of theoretical uncertainties, we find that within the Standard Model, the tensions could be explained if there are unaccounted hadronic effects much larger than our estimates. Assuming hadronic uncertainties are estimated in a sufficiently conservative way, we discuss the implications of the experimental results on new physics, both model independently as well as in the context of the minimal supersymmetric standard model and models with flavour-changing Z′Z' bosons. We discuss in detail the violation of lepton flavour universality as hinted by the current data and make predictions for additional lepton flavour universality tests that can be performed in the future. We find that the ratio of the forward-backward asymmetries in B→K∗μ+μ−B \to K^* \mu^+\mu^- and B→K∗e+e−B \to K^* e^+e^- at low dilepton invariant mass is a particularly sensitive probe of lepton flavour universality and allows to distinguish between different new physics scenarios that give the best description of the current data.Comment: 49 pages, 12 figures. v4: matches version published in EPJ

    Fermion Hierarchy from Sfermion Anarchy

    Get PDF
    We present a framework to generate the hierarchical flavor structure of Standard Model quarks and leptons from loops of superpartners. The simplest model consists of the minimal supersymmetric standard model with tree level Yukawa couplings for the third generation only and anarchic squark and slepton mass matrices. Agreement with constraints from low energy flavor observables, in particular Kaon mixing, is obtained for supersymmetric particles with masses at the PeV scale or above. In our framework both the second and the first generation fermion masses are generated at 1-loop. Despite this, a novel mechanism generates a hierarchy among the first and second generations without imposing a symmetry or small parameters. A second-to-first generation mass ratio of order 100 is typical. The minimal supersymmetric standard model thus includes all the necessary ingredients to realize a fermion spectrum that is qualitatively similar to observation, with hierarchical masses and mixing. The minimal framework produces only a few quantitative discrepancies with observation, most notably the muon mass is too low. We discuss simple modifications which resolve this and also investigate the compatibility of our model with gauge and Yukawa coupling Unification.Comment: 42 pages, 11 figure
    • …
    corecore