4,649 research outputs found
The experimental determination of tyre model parameters
SUMMARY
This report describes the analysis of a series of experiments on pneumatic tyres
which were designed to test the various hypotheses: regarding the deformed shape of a
tyre during the steering process.
The experiments consisted of several separate tests first described in Ref. 1 and 2.
a) The application of a point lateral force or a moment at one position on the tread band
which is restrained at the centre of the wheel, and the measurement of the resulting
lateral deflection of each point of the tyre perimeter.
b) The application of a uniform force around the tyre perimeter on a hollow cylindrical
former and applying a load at the centre of the wheel.
c) Direct determination of tread band tension by cutting the tread band and bridging the
cut by a dynamometer.
d) Estimation of the bending modulus of the tread band by test on sections cut from the
tread band.
The analysis of the experiments is carried out by first transforming the test results
into a Fourier series and determining the spectral content of the bending line with an
harmonic analysis. Transfer functions of beam and string models are derived and applied
to the test results. A method of considering a three parameter model is described
QCD corrections to tri-boson production
We present a computation of the next-to-leading order QCD corrections to the
production of three Z bosons at the LHC. We calculate these corrections using a
completely numerical method that combines sector decomposition to extract
infrared singularities with contour deformation of the Feynman parameter
integrals to avoid internal loop thresholds. The NLO QCD corrections to pp ->
ZZZ are approximately 50%, and are badly underestimated by the leading order
scale dependence. However, the kinematic dependence of the corrections is
minimal in phase space regions accessible at leading order.Comment: 15 pages, 3 figures; typos fixed, references and event listing adde
Light Heavy MSSM Higgs Bosons at Large tan_beta
The region of MSSM Higgs parameter space currently excluded by the CDF
Collaboration, based on an analysis of ~1 fb^-1 of integrated luminosity, is
less than the expected sensitivity. We analyze the potential implications of
the persistence of this discrepancy within the MSSM, assuming that the soft
supersymmetry-breaking contributions to scalar masses are universal, apart from
those to the Higgs masses (the NUHM model). We find that a light heavy MSSM
Higgs signal in the unexcluded part of the sensitive region could indeed be
accommodated in this simple model, even after taking into account other
constraints from cold dark matter, electroweak precision observables and B
physics observables. In this case the NUHM suggests that supersymmetric
signatures should also be detectable in the near future in some other
measurements such as BR(B_s -> mu+ mu-), BR(b -> s gamma) and (g-2)_mu, and M_h
would have to be very close to the LEP exclusion limit. In addition, the dark
matter candidate associated with this model should be on the verge of detection
in direct detection experiments.Comment: 14 pages, 2 figure
CPsuperH2.3: an Updated Tool for Phenomenology in the MSSM with Explicit CP Violation
We describe the Fortran code CPsuperH2.3, which incorporates the following
updates compared with its predecessor CPsuperH2.0. It implements improved
calculations of the Higgs-boson masses and mixing including stau contributions
and finite threshold effects on the tau-lepton Yukawa coupling. It incorporates
the LEP limits on the processes e^+ e^- to H_i Z, H_i H_j and the CMS limits on
H_i to tau^+ tau^- obtained from 4.6/fb of data at a centre-of-mass energy of 7
TeV. It also includes the decay mode H_i to Z gamma and the Schiff-moment
contributions to the electric dipole moments of Mercury and Radium225, with
several calculational options for the case of Mercury. These additions make
CPsuperH2.3 a suitable tool for analyzing possible CP-violating effects in the
MSSM in the era of the LHC and a new generation of EDM experimentsComment: 31 pages, 10 eps figures, 7 tables; H to Z gamma and SM BRs included;
To appear in CPC; Typos in Eq.(A.2) corrected;The program may be obtained
from http://www.hep.man.ac.uk/u/jslee/CPsuperH.html, or by contacting the
first author at [email protected]; A comment added after Eq.(15) and a typo in
Eq.(A.4) correcte
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