54 research outputs found
Z-Decays to b Quarks and the Higgs Boson Mass
A model independent analysis of the most recent averages of precision
electroweak data from LEP and SLD finds a 3 deviation of the parameter
from the Standard Model prediction.
The fitted value of shows a strong dependence on the inclusion or
exclusion of b quark data, and the Standard Model fits have poor confidence
levels of a few percent when the latter are included.
The good fits obtained to lepton data, c quark data and the directly measured
top quark mass, give GeV and indicate that the
Higgs boson mass is most likely less than 200 GeV.Comment: 15 pages, 3 figures, 6 table
Precision Measurements and Fermion Geography in the Randall-Sundrum Model Revisited
We re-examine the implications of allowing fermion fields to propagate in the
five-dimensional bulk of the Randall-Sundrum (RS) localized gravity model. We
find that mixing between the Standard Model top quark and its Kaluza Klein
excitations generates large contributions to the rho parameter and consequently
restricts the fundamental RS scale to lie above 100 TeV. To circumvent this
bound we propose a `mixed' scenario which localizes the third generation
fermions on the TeV brane and allows the lighter generations to propagate in
the full five-dimensional bulk. We show that this construction naturally
reproduces the observed m_c / m_t and m_s / m_b hierarchies. We explore the
signatures of this scenario in precision measurements and future high energy
collider experiments. We find that the region of parameter space that addresses
the hierarchies of fermion Yukawa couplings permits a Higgs boson with a mass
of 500 GeV and remains otherwise invisible at the LHC. However, the entire
parameter region consistent with electroweak precision data is testable at
future linear colliders. We briefly discuss possible constraints on this
scenario arising from flavor changing neutral currents.Comment: 44 pages, 20 ps files; VII, typos fixed and refs adde
RooStatsCms: a tool for analyses modelling, combination and statistical studies
The RooStatsCms (RSC) software framework allows analysis modelling and
combination, statistical studies together with the access to sophisticated
graphics routines for results visualisation. The goal of the project is to
complement the existing analyses by means of their combination and accurate
statistical studies.Comment: Proceedings of the 11th Topical Seminar on Innovative Particle and
Radiation Detectors. 4 pages and 5 figure
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