210 research outputs found
Single Top Production and Top Properties at the Tevatron
We summarize recent measurements made at the Tevatron Collider using top
event candidates. Cross section and mass measurements are discussed in a
separate contribution to these Proceedings. Here we report on studies of the
top P distribution in \ttbar production and studies of single top
production. Properties of top decays examined are:
BF(t \into Wb)/BF(t \into Wq), helicity amplitudes of W's from top decays
and correlations of \ttbar decay products. Searches for new physics in rare
top decays and a search for a state X \into \ttbar are also reported.Comment: 19 pages including 9 figures. Proceedings of the 1999 Lathuile
Conferenc
Precision measurements of the top quark mass from the Tevatron in the pre-LHC era
The top quark is the heaviest of the six quarks of the Standard Model.
Precise knowledge of its mass is important for imposing constraints on a number
of physics processes, including interactions of the as yet unobserved Higgs
boson. The Higgs boson is the only missing particle of the Standard Model,
central to the electroweak symmetry breaking mechanism and generation of
particle masses. In this Review, experimental measurements of the top quark
mass accomplished at the Tevatron, a proton-antiproton collider located at the
Fermi National Accelerator Laboratory, are described. Topologies of top quark
events and methods used to separate signal events from background sources are
discussed. Data analysis techniques used to extract information about the top
mass value are reviewed. The combination of several most precise measurements
performed with the two Tevatron particle detectors, CDF and \D0, yields a value
of \Mt = 173.2 \pm 0.9 GeV/.Comment: This version contains the most up-to-date top quark mass averag
Combined Forward-Backward Asymmetry Measurements in Top-Antitop Quark Production at the Tevatron
The CDF and D0 experiments at the Fermilab Tevatron have measured the asymmetry between yields of forward- and backward-produced top and antitop quarks based on their rapidity difference and the asymmetry between their decay leptons. These measurements use the full data sets collected in proton-antiproton collisions at a center-of-mass energy of TeV. We report the results of combinations of the inclusive asymmetries and their differential dependencies on relevant kinematic quantities. The combined inclusive asymmetry is . The combined inclusive and differential asymmetries are consistent with recent standard model predictions
Search for large extra dimensions in the production of jets and missing transverse energy in p(p)over-bar collisions at root s=1.96 TeV
We present the results of a search for new physics in the jets plus missing transverse energy data sample collected from 368 pb(-1) of p (p) over bar collisions at root s = 1.96 TeV recorded by the Collider Detector at Fermilab. We compare the number of events observed in the data with a data-based estimate of the standard model backgrounds contributing to this signature. We observe no significant excess of events, and we interpret this null result in terms of lower limits on the fundamental Planck scale for a large extra dimensions scenario
Measurement of the W+W- production cross section in p(p)over-bar collisions at root s=1.96 TeV using dilepton events
We present a measurement of the W+W- production cross section using 184 pb(-1) of p (p) over bar collisions at a center-of-mass energy of 1.96 TeV collected with the Collider Detector at Fermilab. Using the dilepton decay channel W+W-→ l(+)ν l(-)(ν) over bar, where the charged leptons can be either electrons or muons, we find 17 candidate events compared to an expected background of 5.0(-0.8)(+2.2) events. The resulting W+W- production cross-section measurement of σ(p (p) over bar → W+W-)=14.6(-5.1)(+5.8)(stat)(-3.0)(+1.8)(syst)± 0.9(lum) pb agrees well with the standard model expectation
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