3,016 research outputs found

    Constraints on Weakly Mixed Sterile Neutrinos in the Light of SNO Salt Phase and 766.3 Ty KamLAND Data

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    The possibility of flavor transitions into sterile neutrinos (accompanying the dominant LMA transitions) in the solar boron neutrino flux has been examined in a scenario proposed by Hollanda and Smirnov to overcome some generic problems of the pure LMA scenario. It is found that the most recent SNO salt phase solar neutrino data and the KamLAND 766.3 Ty spectral data, allow for a significant sterile presence in the solar boron neutrino flux reaching the earth.Comment: 12 pages, 4 figure

    Finite element structural model of a large, thin, completely free, flat plate

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    A finite element structural model of a 30.48 m x 30.48 m x 2.54 mm completely free aluminum plate is described and modal frequencies and mode shape data for the first 44 modes are presented. An explanation of the procedure for using the data is also presented. The model should prove useful for the investigation of controller design approaches for large flexible space structures

    Predictions for the unitarity triangle angles in a new parametrization

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    A new approach to the parametrization of the CKM matrix, VV, is considered in which VV is written as a linear combination of the unit matrix II and a non-diagonal matrix UU which causes intergenerational-mixing, that is V=cosθI+isinθUV=\cos\theta I+i\sin\theta U. Such a VV depends on 3 real parameters including the parameter θ\theta. It is interesting that a value of θ=π/4\theta=\pi/4 is required to fit the available data on the CKM-matrix including CP-violation. Predictions of this fit for the angles α\alpha, β\beta and γ\gamma for the unitarity triangle corresponding to V11V13+V21V23+V31V33=0V_{11}V^*_{13} + V_{21} V^*_{23} +V_{31}V^*_{33} =0, are given. For θ\theta=π/4\pi/4, we obtain α=88.46\alpha=88.46^\circ, β=45.046\beta=45.046^\circ and γ=46.5\gamma=46.5^\circ. These values are just about in agreement, within errors, with the present data. It is very interesting that the unitarity triangle is expected to be approximately a right-angled, isosceles triangle. Our prediction sin2β=1\sin 2\beta = 1 is in excellent agreement with the value 0.99±0.15±0.050.99\pm 0.15\pm 0.05 reported by the Belle collaboration at the Lepton-Photon 2001 meeting.Comment: 11 pages, latex, no figure

    Analysis and simulation of a magnetic bearing suspension system for a laboratory model annular momentum control device

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    A linear analysis and the results of a nonlinear simulation of a magnetic bearing suspension system which uses permanent magnet flux biasing are presented. The magnetic bearing suspension is part of a 4068 N-m-s (3000 lb-ft-sec) laboratory model annular momentum control device (AMCD). The simulation includes rigid body rim dynamics, linear and nonlinear axial actuators, linear radial actuators, axial and radial rim warp, and power supply and power driver current limits

    On the D0D^0 -- DsD_s lifetime difference and τ7π+ντ\tau\to 7\pi + \nu_\tau decays

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    In this paper we discuss some aspects of inclusive decays of charmed mesons and also decays of the τ\tau lepton into ντ+7π\nu_\tau + 7\pi. We find that phase space effects are likely to explain the observed lifetime ratio τ(Ds+)/τ(D0)\tau(D_s^+) / \tau(D^0) = 1.17. In particular one need not appeal to a large annihilation contribution in the inclusive D0D^0 decay which, being absent in Ds+D_s^+ decays could also contribute to the enhanced D0D^0 decay rate relative to that of the Ds+D_s^+. Examining a separate problem, we find that the rate for τντ+7π\tau\to \nu_\tau + 7\pi is almost completely dominated by the tiny phase space for the final eight particle state. Using an effective chiral Lagrangian to estimate the matrix element yields a branching ratio into the channel of interest far smaller than the present upper bound.Comment: No figure

    Quantum Corrections to Newton's Law

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    We present a new approach to quantum gravity starting from Feynman's formulation for the simplest example, that of a scalar field as the representative matter. We show that we extend his treatment to a calculable framework using resummation techniques already well-tested in other problems. Phenomenological consequences for Newton's law are described.Comment: 7 pages, 1 figure; improved fig., refs;improved discussion;more discussion; proo

    Intrinsic Charm Flavor and Helicity Content in the Proton

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    Contributions to the quark flavor and spin observables from the intrinsic charm in the proton are discussed in the SU(4) quark meson fluctuation model. Our results suggest that the probability of finding the intrinsic charm in the proton is less than 1%. The intrinsic charm helicity is small and negative, Δc(0.0030.015)\Delta c \simeq -(0.003\sim 0.015). The fraction of the total quark helicity carried by the intrinsic charm is less than 2%, and c_\up/c_\dw=35/67.Comment: 4 pages, 2 tables (revised version

    Concurrent Image Processing Executive (CIPE). Volume 1: Design overview

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    The design and implementation of a Concurrent Image Processing Executive (CIPE), which is intended to become the support system software for a prototype high performance science analysis workstation are described. The target machine for this software is a JPL/Caltech Mark 3fp Hypercube hosted by either a MASSCOMP 5600 or a Sun-3, Sun-4 workstation; however, the design will accommodate other concurrent machines of similar architecture, i.e., local memory, multiple-instruction-multiple-data (MIMD) machines. The CIPE system provides both a multimode user interface and an applications programmer interface, and has been designed around four loosely coupled modules: user interface, host-resident executive, hypercube-resident executive, and application functions. The loose coupling between modules allows modification of a particular module without significantly affecting the other modules in the system. In order to enhance hypercube memory utilization and to allow expansion of image processing capabilities, a specialized program management method, incremental loading, was devised. To minimize data transfer between host and hypercube, a data management method which distributes, redistributes, and tracks data set information was implemented. The data management also allows data sharing among application programs. The CIPE software architecture provides a flexible environment for scientific analysis of complex remote sensing image data, such as planetary data and imaging spectrometry, utilizing state-of-the-art concurrent computation capabilities

    Has the anomalous single production of the fourth SM family quarks decaying into light Higgs boson been observed by CDF?

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    Superjet events observed by the CDF Collaboration are interpreted as anomalous single production of the fourth SM family u_4 quark, decaying into a new light scalar particle. The specific predictions of the proposed mechanism are discussed.Comment: 5 pages, 1 tabl
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