5,956 research outputs found

    The Polarized Two-Loop Massive Pure Singlet Wilson Coefficient for Deep-Inelastic Scattering

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    We calculate the polarized massive two--loop pure singlet Wilson coefficient contributing to the structure functions g1(x,Q2)g_1(x,Q^2) analytically in the whole kinematic region. The Wilson coefficient contains Kummer--elliptic integrals. We derive the representation in the asymptotic region Q2m2Q^2 \gg m^2, retaining power corrections, and in the threshold region. The massless Wilson coefficient is recalculated. The corresponding twist--2 corrections to the structure function g2(x,Q2)g_2(x,Q^2) are obtained by the Wandzura--Wilczek relation. Numerical results are presented.Comment: 22 pages Latex, 8 Figure

    Review of the Supply of and Demand for Further Education in Scotland

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    These documents provide are an Executive Summary and Full Report of the background to, methodology for, and overall conclusions and recommendations of a review of the supply of and demand for Further Education (FE) provision in Scottish Further Education colleges in 2000. The review was commissioned by the Scottish Further Education Funding Council (SFEFC), and carried out between November 1999 and June 2000 by a team of researchers drawn from the Scottish Further Education Unit (SFEU), the Centre for Research in Lifelong Learning, Glasgow Caledonian University/University of Stirling, and the Applied Statistics Group, Napier University

    Measured limits to contamination of optical surfaces by elastomers in vacuum

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    We have monitored the reflectivity of mirrors that were exposed to a fluoroelastomer (3M-Fluorel 2176) and a room-temperature vulcanizing silicone rubber (RTV-615) in vacuum. The 95% confidence limit on the decrease of mirror reflectivities was less than 0.35 ppm/week for Fluorel and <0.29 ppm@week for RTV-615

    On the origin dependence of multipole moments in electromagnetism

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    The standard description of material media in electromagnetism is based on multipoles. It is well known that these moments depend on the point of reference chosen, except for the lowest order. It is shown that this "origin dependence" is not unphysical as has been claimed in the literature but forms only part of the effect of moving the point of reference. When also the complementary part is taken into account then different points of reference lead to different but equivalent descriptions of the same physical reality. This is shown at the microscopic as well as at the macroscopic level. A similar interpretation is valid regarding the "origin dependence" of the reflection coefficients for reflection on a semi infinite medium. We show that the "transformation theory" which has been proposed to remedy this situation (and which is thus not needed) is unphysical since the transformation considered does not leave the boundary conditions invariant.Comment: 14 pages, 0 figure

    Shot Noise in Gravitational-Wave Detectors with Fabry-Perot Arms

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    Shot-noise-limited sensitivity is calculated for gravitational-wave interferometers with Fabry–Perot arms, similar to those being installed at the Laser Interferometer Gravitational-Wave Observatory (LIGO) and the Italian–French Laser Interferometer Collaboration (VIRGO) facility. This calculation includes the effect of nonstationary shot noise that is due to phase modulation of the light. The resulting formula is experimentally verified by a test interferometer with suspended mirrors in the 40-m arms

    The unpolarized two-loop massive pure singlet Wilson coefficients for deep-inelastic scattering

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    We calculate the massive two--loop pure singlet Wilson coefficients for heavy quark production in the unpolarized case analytically in the whole kinematic region and derive the threshold and asymptotic expansions. We also recalculate the corresponding massless two--loop Wilson coefficients. The complete expressions contain iterated integrals with elliptic letters. The contributing alphabets enlarge the Kummer-Poincar\'e letters by a series of square-root valued letters. A new class of iterated integrals, the Kummer-elliptic integrals, are introduced. For the structure functions F2F_2 and FLF_L we also derive improved asymptotic representations adding power corrections. Numerical results are presented.Comment: 42, pages Latex, 8 Figure

    The O(α2)O(\alpha^2) Initial State QED Corrections to e+ee^+e^- Annihilation to a Neutral Vector Boson Revisited

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    We calculate the non-singlet, the pure singlet contribution, and their interference term, at O(α2)O(\alpha^2) due to electron-pair initial state radiation to e+ee^+ e^- annihilation into a neutral vector boson in a direct analytic computation without any approximation. The correction is represented in terms of iterated incomplete elliptic integrals. Performing the limit sme2s \gg m_e^2 we find discrepancies with the earlier results of Ref.~\cite{Berends:1987ab} and confirm results obtained in Ref.~\cite{Blumlein:2011mi} where the effective method of massive operator matrix elements has been used, which works for all but the power corrections in m2/sm^2/s. In this way, we also confirm the validity of the factorization of massive partons in the Drell-Yan process. We also add non-logarithmic terms at O(α2)O(\alpha^2) which have not been considered in \cite{Berends:1987ab}. The corrections are of central importance for precision analyzes in e+ee^+e^- annihilation into γ/Z\gamma^*/Z^* at high luminosity.Comment: 4 pages Latex, 2 Figures, several style file

    Položaj i razvitak svjetske čelične industrije

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    In the article, the view to the position and development of the global steel industry is commented using the experience of last 20 years of evolution of the Czech steel industry. The changes are observed in the scope of production, consumption, and trade.Položaj i razvitak svjetske čelične industrije. Na temelju iskustva posljednih 20-ak godina ustroja češke čelične industrije, u članku se daje osvrt na položaj i razvitak svjetske čelične industrije. Promjene se motre u dosezima proizvodnje, potrošnje i prodaje

    Položaj i razvitak svjetske čelične industrije

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    In the article, the view to the position and development of the global steel industry is commented using the experience of last 20 years of evolution of the Czech steel industry. The changes are observed in the scope of production, consumption, and trade.Položaj i razvitak svjetske čelične industrije. Na temelju iskustva posljednih 20-ak godina ustroja češke čelične industrije, u članku se daje osvrt na položaj i razvitak svjetske čelične industrije. Promjene se motre u dosezima proizvodnje, potrošnje i prodaje

    Taking stock of policy networks:Do they matter?

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