4,860 research outputs found
12 Years of Precision Calculations for LEP. What's Next?
I shortly review time period of twelve years, 1989-2000, which was devoted to
a theoretical support of experiments at LEP and SLC at Z resonance and discuss
several directions of possible future work in the field of precision
theoretical calculations for experiments at future colliders.Comment: 11 Latex, including 1 figures. Updated version as appeared in the
Journa
The American National Exhibition and Kitchen Debates: How the World\u27s Superpowers Portrayed the Events of the Summer of 1959 to Meet National Needs
An undergraduate research paper centered on the investigation of American and Soviet propaganda efforts during and immediately after the Kitchen Debate of 1959
Project {\tt SANC} (former {\tt CalcPHEP}): Support of Analytic and Numeric calculations for experiments at Colliders
The project, aimed at the theoretical support of experiments at modern and
future accelerators -- TEVATRON, LHC, electron Linear Colliders (TESLA, NLC,
CLIC) and muon factories, is presented. Within this project a four-level
computer system is being created, which must automatically calculate, at the
one-loop precision level the pseudo- and realistic observables (decay rates and
event distributions) for more and more complicated processes of elementary
particle interaction, using the principle of knowledge storing.
It was already used for a recalculation of the EW radiative corrections for
Atomic Parity Violation [1] and complete one-loop corrections for the process
[2-4]; for the latter an, agreement up to 11 digits with
FeynArts and the other results is found. The version of {\tt SANC} that we
describe here is capable of automatically computing the decay rates and the
distributions for the decays in the one-loop
approximation.Comment: 3 Latex, Presented at ICHEP2002, Amsterdam, July 24-30, 2000;
Submitted to Proceeding
J_AW,WA functions in Passarino-Veltman reduction
In this paper we continue to study a special class of Passarino-Veltman
functions J arising at the reduction of infrared divergent box diagrams. We
describe a procedure of separation of two types of singularities, infrared and
mass singularities, which are absorbed in simple C0 functions. The infrared
divergences of C0's can be regularized then by any method: photon mass,
dimensionally or by the width of an unstable particle. Functions J, in turn,
are represented as certain linear combinations of the standard D0 and C0
Passarino-Veltman functions. The former are free of both types of singularities
and are expressed as explicit and compact linear combinations of logarithms and
dilogarithm functions. We present extensive comparisons of numerical results
with those obtained with the aid of the LoopTools package
Off shell W pair production in e+ e- annihilation: The CC11 process
The various four-fermion production channels in annihilation are
discussed and the {\tt CC11} process , {\mbox{}}, is studied in detail. The cross
section , with being the invariant masses squared
of the two fermion pairs, may be expressed by six generic functions. All but
one may be found in the literature. The cross section, including initial state
radiation and the Coulomb correction, is discussed and compared with other
calculations from low energies up to = 2 ~TeV.Comment: 28 pages, LaTex, 6 figures, 8 tables, a uuencoded file containing the
latex file and figures is available via anonymous ftp at
ftp://ftp.ifh.de/pub/preprint/desy95-167.uu and the complete ps file also
from http://www.ifh.de/~riemann/desy95-167.ps.g
An electroweak library for the calculation of EWRC to e+ e- --> f fbar within the CalcPHEP project
We present a description of calculations of the electroweak amplitude for e+
e- --> f fbar process. The calculations are done within the OMS (on-mass-shell)
renormalization scheme in two gauges: in Rxi, which allows an explicit control
of gauge invariance by examining cancellation of gauge parameters and search
for gauge-invariant subsets of diagrams, and in the unitary gauge as a
cross-check. The formulae we derived are realized in a FORTRAN code eeffLib,
which is being created within the framework of the project CalcPHEP. We present
a comprehensive comparison between eeffLib results for the light top with
corresponding results of the well-known program ZFITTER for the u ubar channel,
as well as a preliminary comparison with results existing in the world
literature.Comment: Revised version, 47 Latex, including 14 figures (2 eps figures), 5
table
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