相关论文: Noncommutative Standard Model in Top Quark Sector
We review recent measurements of the properties of the top quark by the D0 experiment: the decay width of the top quark, the CKM matrix element $V_{tb}$, the helicity of the $W$ boson, anomalous couplings at the $Wtb$ vertex, violation of…
The search for the electroweak production of top quarks is entering an exciting time: with the ever increasing luminosity furnished by the Tevatron ppbar Collider at Fermilab and sophisticated analysis techniques we are now able to approach…
An overview of the recent measurements of the top antitop quark pair production cross section in proton antiproton collisions at \sqrt{s}=1.96 TeV in lepton + jets and dilepton final states is presented. These measurements are based on 1 --…
Recent analysis of the combined data of cosmic microwave background, galaxy clustering and supernovae type Ia observations have set strong constraints on the equation of state parameter $w_X$. The upper bound $w_X < -0.82$ at 95% c.l. rules…
The CCFR collaboration reports a precise measurement of electroweak parameters derived from the ratio of neutral-current to charged-current cross-sections in neutrino-nucleon scattering at the Fermilab Tevatron. This ratio of cross-sections…
We present a measurement of the electric charge of top quarks using $t\bar{t}$ events produced in $p\bar{p}$ collisions at the Tevatron. The analysis is based on fully reconstructed $t\bar{t}$ pairs in lepton+jets final states. Using data…
We study the spin properties of top quarks produced in collisions of polarized photons in the threshold region. For a relatively heavy top quark the influence of non-perturbative effects is small and its polarization parameters can be…
Constraints on models which predict resonant top-quark pair production at the LHC are provided via a reinterpretation of the Standard Model (SM) particle level measurement of the top-anti-top invariant mass distribution, $m(t\bar{t})$. We…
We present a precision measurement of the top-quark mass using the full sample of Tevatron $\sqrt{s}=1.96$ TeV proton-antiproton collisions collected by the CDF II detector, corresponding to an integrated luminosity of 8.7 $fb^{-1}$. Using…
Top quark decays before hadronization and its information transfer to final products. The top quark decays via the weak interaction, hence the azimuthal polarized decay rate is zero in the leading order of SM. Therefore the study of top…
Precision studies of top quark properties provide a unique playground to test the predictions of the standard model and to search for new physics. Reviewed results from the CMS experiment done with the data collected at 8 TeV include…
We propose the Z -> gamma gamma decay, a process strictly forbidden in the standard model, as a signal suitable for the search of noncommutativity of coordinates at very short distances. We compute the Z -> gamma gamma partial widthin the…
Ten years after its discovery at the Tevatron collider, we still know little about the top quark. Its large mass suggests it may play a key role in the mechanism of Electroweak Symmetry Breaking (EWSB), or open a window of sensitivity to…
The CDF and D0 collaborations at Fermilab's Tevatron p-pbar collider have in place an extensive program to measure fundamental properties of the top quark. Recent results from Run I (sqrt-s = 1.8 TeV) and Run II (sqrt-s = 1.96 TeV) on the…
In this letter, we summarize the latest results of the top-quark production and properties at the Tevatron. We do not include results of the top-quark mass and single top-quark production as they were presented in separate talks. The…
The new measurement of the $W$-boson mass from the CDF collaboration shows a significant tension with the Standard Model prediction. We quantify this discrepancy within a state-of-the-art analysis of electroweak precision data and…
We present a quantitative study on sensitivities to the top-decay anomalous couplings, taking into account realistic experimental conditions expected at Tevatron and LHC. A double angular distribution of W and charged lepton in the top…
Recent cosmological observations hint at a deviation from the simple power-law form of the primordial spectrum of curvature perturbations. In this paper we show that in the presence of a tensor component, a turn-over in the initial spectrum…
The nontrivial boundary conditions (BC's) for the Topcolor breaking are investigated in the context of the TeV-scale extra dimension scenario. In the gauge symmetry breaking mechanism via the BC's we do not need to incorporate a dynamical…
We adopt a Markov Chain Monte Carlo method to examine various new physics models which can generate the forward-backward asymmetry in top quark pair production observed at the Tevatron by the CDF Collaboration. We study the following new…