Related papers: Below Threshold $Z'$ Mass and Coupling Determinati…
The determination of the $Zb\bar{b}$ coupling in experiments has been a long-standing challenge, as the limited precision of off $Z$-pole measurements at the LEP has resulted in two degenerate solutions remained to be resolved. In this…
The first study of W boson production in pPb collisions is presented, for bosons decaying to a muon or electron, and a neutrino. The measurements are based on a data sample corresponding to an integrated luminosity of 34.6 inverse nanobarns…
In this paper, we consider a single top quark production in association with a neutral gauge boson (Z boson or Photon) at the future electron-positron colliders. We utilize these channels to probe the top quark Flavour Changing Neutral…
A weakly coupled new neutral gauge boson, forming a narrow resonance, can be efficiently produced at e+e- colliders through radiative return processes if the collider energy is larger than the gauge boson mass. This contribution analyzes…
We determine the mass of the bottom quark from high moments of the bottom production cross section in e+ e- annihilation, which are dominated by the threshold region. On the theory side next-to-next-to-next-to-leading order (NNNLO)…
The study of charged and neutral boson vertices has been performed in different production channels at the LEP experiments. Decay rates and kinematic properties of these events are exploited to set constraints on the corresponding gauge…
The Next Linear Collider(NLC) will provide a excellent tool for probing the detailed nature of the top quark. By extending the recent analysis of Dokshitzer, Khoze and Sterling, we perform a preliminary examination of the influence of an…
If there is an extra U(1) gauge symmetry broken at low energies, then it may be possible from the charges of the known quarks and leptons under this U(1) to make inferences about how much gauge unification occurs at high scales and about…
A scan of the top production threshold at a future electron-positron collider provides the possibility for a precise measurement of the top quark mass in theoretically well-defined mass schemes. With statistical uncertainties of 20 MeV or…
The production of Z boson pairs in proton-proton (pp) collisions, pp $\to$ (Z/$\gamma^*$)(Z/$\gamma^*$) $\to$ 2$\ell$ 2$\ell'$, where $\ell,\ell'$ = e or $\mu$, is studied at a center-of-mass energy of 13 TeV with the CMS detector at the…
I first review a few basic guiding principles that lead to the notion of a hierarchy of couplings in searches of New Physics involving weak bosons processes. The hierarchies within a linear and a non-linear realization of symmetry breaking…
W-pair production in e+ e- annihilation at 500 GeV is studied using different Monte Carlo generators and the proposed detector for the Linear Collider in its TESLA version. Semileptonic W decays are used to give hints for the detector…
We discuss three promising diagnostic probes of the couplings of a possible heavy $Z'$ boson at hadron colliders: the forward-backward asymmetry into leptons, the rare decay $Z' \ra W^{\pm} \ell^{\mp} \nu$, and associated production $pp \ra…
Heavy neutral gauge bosons, Z's, are predicted by many theoretical schemes of physics beyond the Standard Model, and intensive searches for their signatures will be performed at present and future high energy colliders. It is quite possible…
The littlest Higgs (LH) model predicts the existence of the new gauge bosons $Z'$ and $B'$. We calculate the contributions of these new particles to the processes $e^{+}e^{-}\to\bar{f}f$ with $f=\tau, \mu, b,$ or $c$ and study the…
We study the flavor changing neutral current couplings of new heavy quarks through the Z' models at the LHC. We calculate the cross sections for the signal and the corresponding standard model background processes. Considering the present…
We investigate the potential of short-baseline experiments in order to measure the dispersion relation of the (muon) neutrino, with a prospect of eventually measuring the neutrino mass. As a byproduct, the experiment would help to constrain…
It is possible to place constraints on non-Standard-Model gauge-boson self-couplings and other new physics by studying their one-loop contributions to precisely measured observables. We extend previous analyses which constrain such…
Top quark production in the process $e^+e^- \rightarrow t\bar{t}$ at a future linear electron positron collider with polarized beams is a powerful tool to determine the scale of new physics. Studies at the $\ttbar$ threshold will allow for…
A search for heavy neutral gauge bosons (Z') decaying into a pair of tau leptons is performed in proton-proton collisions at $\sqrt{s}$ = 13 TeV at the CERN LHC. The data were collected with the CMS detector and correspond to an integrated…