971 research outputs found
Top Quark Properties at the TeVatron
Discovered in 1995 by CDF and D0 at the Fermilab Tevatron collider, the top
quark remains interesting to test the Standard Model. Having collected more
than 7 fb of integrated luminosity with both experiments until today,
several top quark properties have been measured with increasing precision,
while other properties have been investigated for the first time. In this
article recent measurements of top quark properties from CDF and D0 are
presented, using between 1 fb and 4.8 fb of data. In particular,
the measurement of the top quark mass, the top quark width, the top antitop
mass difference, a check of the electric charge of the top quark, measurements
of the top antitop quark spin correlation and W helicity as well as a search
for charged Higgs bosons are discussed.Comment: 6 pages, Presented at the 2010 Rencontres de Moriond EW, La Thuile,
Aosta Valley, Italy, 06-13 Mar 201
Beyond the Standard Model searches with top quarks at D0
Due to its high mass and short lifetime, the top quark plays an important
role in checking the Standard Model of particle physics. In this report, we pr\
esent a variety of searches for physics beyond the Standard Model, involving
top quarks, at the D0 detector at the Fermilab Tevatron collider. Specifically,
we present searches in top quark pair production, single top quark production
and top quark decays. The search spectra discussed here involve a search for
resonances, associated production of Higgs bosons and ,
charged Higgs bosons and heavy gauge bosons. Furthermore, we measure
the forward-backward charge asymmetry and a ratio of branching fractions.Comment: To appear in the proceedings of 2009 Europhysics Conference on High
Energy Physics: HEP 2009 (EPS-HEP 2009), Cracow, Poland, 16-22 Jul 2009. 5
pages, 2 figures
Top Quark Properties
Since its discovery in 1995 by the CDF and D0 collaborations at the Fermilab
Tevatron collider, the top quark has undergone intensive studies. Besides the
Tevatron experiments, with the start of the LHC in 2010 a top quark factory
started its operation. It is now possible to measure top quark properties
simultaneously at four different experiments, namely ATLAS and CMS at LHC and
CDF and D0 at Tevatron. Having collected thousands of top quarks each, several
top quark properties have been measured precisely, while others are being
measured for the first time. In this article, recent measurements of top quark
properties from ATLAS, CDF, CMS and D0 are presented, using up to 5.4 fb-1 of
integrated luminosity at the Tevatron and 1.1 fb^-1 at the LHC. In particular,
measurements of the top quark mass, mass difference, forward backward charge
asymmetry, tt - spin correlations, the ratio of branching fractions, W
helicity, anomalous couplings, color flow and the search for flavor changing
neutral currents are discussed.Comment: 8 pages, 1 figure, proceedings for the PIC2011 conference, Vancouver,
BC, Canad
Top Quark Mass Measurements at the Tevatron
Since the discovery of the top quark in 1995 by the CDF and D0 collaborations
at the Fermilab Tevatron proton antiproton collider, precise measurements of
its mass are ongoing. Using data recorded by the D0 and CDF experiment,
corresponding to up to the full Tevatron data sample, top quark mass
measurements performed in different final states using various extraction
techniques are presented in this article. The recent Tevatron top quark mass
combination yields m_t=173.20 +-0.87 GeV. Furthermore, measurements of the top
antitop quark mass difference from the Tevatron are discussed.Comment: 6 pages, 2 figures, presented at EPS-HEP 2013, Stockholm, Sweden,
July 18-24, 201
Tevatron Top-Quark Combinations and World Top-Quark Mass Combination
Almost 20 years after its discovery, the top quark is still an interesting
particle, undergoing precise investigation of its properties. For many years,
the Tevatron proton antiproton collider at Fermilab was the only place to study
top quarks in detail, while with the recent start of the LHC proton proton
collider a top quark factory has opened. An important ingredient for the full
understanding of the top quark is the combination of measurements from the
individual experiments. In particular, the Tevaton combinations of single
top-quark cross sections, the ttbar production cross section, the W helicity in
top-quark decays as well as the Tevatron and the world combination of the
top-quark mass are discussed.Comment: 5 pages, 2 figures, to appear in the proceedings of Top2014, Cannes,
France (28th Sept - 3rd Oct 2014
V+jets Background and Systematic Uncertainties in Top Quark Analyses
Vector boson production in association with jets is an important process to
test perturbative quantum chromodynamics and also a background process in top
quark analyses. Measurements on vector boson production in association with
light and heavy flavour jets are presented, performed by the D0 and CDF
collaborations at the Tevatron as well as the ATLAS and CMS experiments at LHC.
Techniques applied in top quark analyses to estimate the vector boson+jets
background are also discussed.Comment: 10 pages, 4 figures; Proceedings of the 6th International Workshop on
Top Quark Physics (TOP13), Durbach, Germany, September 14-19, 201
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