32,343 research outputs found

    Design of helicopter rotor blades for optimum dynamic characteristics

    Get PDF
    The mass and stiffness distributions for helicopter rotor blades are tailored in such a way to give a predetermined placement of blade natural frequencies. The optimal design is pursued with respect of minimum weight, sufficient inertia, and reasonable dynamic characteristics. Finite element techniques are used as a tool. Rotor types include hingeless, articulated, and teetering

    Baryonic contributions to the dilepton spectra in relativistic heavy ion collisions

    Get PDF
    We investigate the baryonic contributions to the dilepton yield in high energy heavy ion collisions within the context of a transport model. The relative contribution of the baryonic and mesonic sources are examined. It is observed that most dominant among the baryonic channels is the decay of N*(1520) and mostly confined in the region below the rho peak. In a transport theory implementation we find the baryonic contribution to the lepton pair yield to be small.Comment: 11 pages, 8 figure

    Design of helicopter rotor blades for optimum dynamic characteristics

    Get PDF
    The possibilities and limitations of tailoring blade mass and stiffness distributions to give an optimum blade design in terms of weight, inertia, and dynamic characteristics are discussed. The extent that changes in mass of stiffness distribution can be used to place rotor frequencies at desired locations is determined. Theoretical limits to the amount of frequency shift are established. Realistic constraints on blade properties based on weight, mass, moment of inertia, size, strength, and stability are formulated. The extent that the hub loads can be minimized by proper choice of E1 distribution, and the minimum hub loads which can be approximated by a design for a given set of natural frequencies are determined. Aerodynamic couplings that might affect the optimum blade design, and the relative effectiveness of mass and stiffness distribution on the optimization procedure are investigated

    LFV in semileptonic τ\tau decays and μe\mu-e conversion in nuclei in SUSY-seesaw

    Full text link
    Here we review the main results of LFV in the semileptonic tau decays τμPP\tau \to \mu PP (PP=π+π,π0π0,K+K,K0Kˉ0PP = \pi^+ \pi^-, \pi^0 \pi^0, K^+ K^-, K^0 \bar{K}^0), τμP\tau \to \mu P (P=π,η,ηP = \pi, \eta, \eta^{\prime}), and τμV\tau \to \mu V (V=ρ,ϕV = \rho, \phi) as well as in μe\mu-e conversion in nuclei within SUSY-seesaw scenarios, and compare our predictions with the present experimental boundsComment: Talk given by M. J. Herrero in SUSY08 conference, Seou

    The muon g-2 discrepancy: errors or new physics?

    Full text link
    After a brief review of the muon g-2 status, we discuss hypothetical errors in the Standard Model prediction that could explain the present discrepancy with the experimental value. None of them looks likely. In particular, an hypothetical increase of the hadroproduction cross section in low-energy e^+e^- collisions could bridge the muon g-2 discrepancy, but is shown to be unlikely in view of current experimental error estimates. If, nonetheless, this turns out to be the explanation of the discrepancy, then the 95% CL upper bound on the Higgs boson mass is reduced to about 130 GeV which, in conjunction with the experimental 114.4 GeV 95% CL lower bound, leaves a narrow window for the mass of this fundamental particle.Comment: 4 pages. Invited talk at 16th International Conference on Supersymmetry and the Unification of Fundamental Interactions (SUSY08), June 16-21 2008, Seoul, Kore
    corecore