3,334 research outputs found

    The Publication Patterns of the Elite Economics Departments: 1995-2000

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    We examine publication patterns of the top seven U.S. economics departments from 1995 to 2000. We construct a departmental-based journal ranking on both the number of publications and the percentage of journal pages from authors affiliated with top institutions. The data show that publications are highly concentrated among a few journals: seven journals comprise more than one-fourth of aggregate research output for the sample. Nine of the eighty-seven most common publication outlets originated in the 1990s. A departmental measure of journal quality avoids the problems confronting citations data. We suggest that economists reconsider the prestige of journals based on these strikingly different results.Economics Departments; Economics; Journals

    D_{sJ}(2860) as the first radial excitation of the D_{s0}^*(2317)

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    A coupled-channel model previously employed to describe the narrow Ds0∗D_{s0}^*(2317) and broad D0∗D_0^*(2400) charmed scalar mesons is generalized so as to include all ground-state pseudoscalar-pseudoscalar and vector-vector two-meson channels. All parameters are chosen fixed at published values, except for the overall coupling constant, which is fine-tuned to reproduce the Ds0∗D_{s0}^*(2317) mass. Thus, the radial excitations Ds0∗D_{s0}^*(2850) and D0∗D_0^*(2740) are predicted, both with a width of about 50 MeV. The former state appears to correspond to the new DsJD_{sJ}(2860) resonance decaying to DKDK announced by BABAR in the course of this work. Also the D0∗D_0^*(2400) resonance is roughly reproduced, though perhaps with a somewhat too low central resonance peak.Comment: Plain LaTeX, 4 pages, 2 Postscript figures; v2: REVTeX, 4 pages, introduction expanded, "Note added in proof" and references added, figures with more detail and improved quality, version accepted for publication in Physical Review Letter

    Attitude control system

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    An attitude control system is described in which angular rate signals are generated by rate gyros mounted closely adjacent to gimbaled engines at the rear of a vehicle. Error signals representative of a commanded change in vehicle angle or attitude are obtained from a precision inertial platform located in the nose region of the vehicle. The rate gyro derived signals dominate at high frequencies where dynamic effects become significant, and platform signals dominate at low frequencies where precision signals are required for a steady vehicle attitude. The blended signals are applied in a conventional manner to control the gimbaling of vehicle engines about control axes

    Constituent and current quark masses at low chiral energies

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    Light constituent quark masses and the corresponding dynamical quark masses are determined by data, the Quark-Level Linear σ\sigma Model, and infrared QCD. This allows to define effective nonstrange and strange current quark masses which reproduce the experimental pion and kaon masses very accurately, by simple additivity. Moreover, the masses of the light scalar mesons σ(600)\sigma(600) and κ(800)\kappa(800) can be obtained straightforwardly from the constituent quark masses. In contrast, the usual nonstrange and strange current quark masses employed by Chiral Perturbation Theory do not allow a simple quantitative explanation of the pion and kaon masses.Comment: 5 pages, EPL style, accepted for publication in Europhys. Let

    Multichannel calculation of the very narrow Ds0∗(2317)D_{s0}^*(2317) and the very broad D0∗(2300−2400)D_0^*(2300-2400)

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    The narrow Ds0∗D_{s0}^{\ast}(2317) and broad D0∗D_0^{\ast}(2300-2400) charmed scalar mesons and their radial excitations are described in a coupled-channel quark model that also reproduces the properties of the light scalar nonet. All two-meson channels containing ground-state pseudoscalars and vectors are included. The parameters are chosen fixed at published values, except for the overall coupling constant λ\lambda, which is fine-tuned to reproduce the Ds0∗D_{s0}^{\ast}(2317) mass, and a damping constant α\alpha for subthreshold contributions. Variations of λ\lambda and D0∗D_0^{\ast}(2300-2400) pole postions are studied for different α\alpha values. Calculated cross sections for SS-wave DKDK and DπD\pi scattering, as well as resonance pole positions, are given for the value of α\alpha that fits the light scalars. The thus predicted radially excited state Ds0∗′{D_{s0}^*}'(2850), with a width of about 50 MeV, seems to have been observed already.Comment: 3 pages, EPJ LaTeX, 2 Postscript figures, 1 table; parallel talk at the IVth International Conference on Quarks and Nuclear Physics (QNP06), Madrid, 5-10 June 200

    Light Higgs bosons from a strongly interacting Higgs sector

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    The mass and the decay width of a Higgs boson in the minimal standard model are evaluated by a variational method in the limit of strong self-coupling interaction. The non-perturbative technique provides an interpolation scheme between strong-coupling regime and weak-coupling limit where the standard perturbative results are recovered. In the strong-coupling limit the physical mass and the decay width of the Higgs boson are found to be very small as a consequence of mass renormalization. Thus it is argued that the eventual detection of a light Higgs boson would not rule out the existence of a strongly interacting Higgs sector.Comment: 2 figure
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