6,250 research outputs found
The Polarized Two-Loop Massive Pure Singlet Wilson Coefficient for Deep-Inelastic Scattering
We calculate the polarized massive two--loop pure singlet Wilson coefficient
contributing to the structure functions analytically in the whole
kinematic region. The Wilson coefficient contains Kummer--elliptic integrals.
We derive the representation in the asymptotic region , retaining
power corrections, and in the threshold region. The massless Wilson coefficient
is recalculated. The corresponding twist--2 corrections to the structure
function 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
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
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
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
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
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 and we also
derive improved asymptotic representations adding power corrections. Numerical
results are presented.Comment: 42, pages Latex, 8 Figure
The Initial State QED Corrections to Annihilation to a Neutral Vector Boson Revisited
We calculate the non-singlet, the pure singlet contribution, and their
interference term, at due to electron-pair initial state
radiation to 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 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
. 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
which have not been considered in \cite{Berends:1987ab}. The
corrections are of central importance for precision analyzes in
annihilation into at high luminosity.Comment: 4 pages Latex, 2 Figures, several style file
Položaj i razvitak svjetske čelične industrije
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
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
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