相关论文: Boson Pair Productions In $e^+$ $e^-$ Annihilation
The double-radiative process e+e- -> Z gamma gamma -> q q~ gamma gamma, where the two hard photons escape detection at low polar angles into opposite directions, is studied in 0.62/fb of data collected with the L3 detector at LEP at…
We consider the possibility of fingerprinting the presence of heavy additional Z' bosons that arise naturally in extensions of the standard model such as E_6 models and left-right symmetric models, through their mixing with the standard…
We summarize results for the processes $e^-\gamma \to \nu W^-, e^-Z, e^-\gamma$ within the electroweak Standard Model. We discuss the essential features of the corresponding lowest-order cross-sections and present numerical results for the…
Existence of discrepancies between experimental data and Monte Carlo predictions for angular distributions in four-jet production via $e^+e^-$ annihilation has been known for some time at LEP1. As such QCD processes constitute significant…
Production of electroweak bosons in e+e- annihilation into quarks and into leptons at energies much greater than 100 Gev is considered. We account for double-logarithmic contributions to all orders in electroweak couplings. It is assumed…
We study the $B_s \to \pi^+ \pi^-$ and $B_d \to K^+ K^-$ decays in the standard model and the family non-universal $Z^\prime$ model. Since none of the quarks in final states is the same as the initial quark, these decay modes can occur only…
Processes of electron-positron annihilation into a pair of fermions were considered. Forward-backward and left-right asymmetries were studied, taking into account polarization of initial and final particles. Complete 1-loop electroweak…
The cross section for different processes induced by $e^+e^-$ annihilation, in the kinematical limit $\beta_{\mu}\approx\beta_{\pi}=(1-m_{\pi}^2/\epsilon^2)^{1/2}\sim 1$, is calculated taking into account first order corrections to the…
We consider the processes $e^{+}e^{-}\rightarrow \ell^{+} \ell^{\prime -}\nu \bar{\nu}^{\prime}$, including all possible charged lepton combinations, with regard to measuring parameters characterizing the $W$ boson. We calculate at what…
The pair production of Z bosons is studied using the data collected by the L3 detector at LEP in 1998 in e+e- collisions at a centre-of-mass energy of 189 GeV. All the visible final states are considered and the cross section of this…
The process e^+e^- --> Z gamma, where the Z boson decays into hadrons or neutrinos, is studied with data collected with the L3 detector at LEP at centre-of-mass energies from 189 GeV up to 209 GeV. The cross sections are measured and found…
A summary of results obtained from e^+e^- annihilations at LEP is given. The precision measurements around the Z resonance, the results from charged gauge boson production and searches for new particles are reviewed. Particular emphasis is…
Measurements are presented of the polarisation of W+W- boson pairs produced in e+e- collisions, and of CP-violating WWZ and WWGamma trilinear gauge couplings. The data were recorded by the OPAL experiment at LEP during 1998, where a total…
A detailed analysis of $Z^{'0}Z^{'0}$, $K^{+}K^{-}$ and $K^{0}\bar{K}^{0}$ pair production in $e^{+}e^{-}$ collisions is presented by using helicity amplitudes. The trilinear bosons couplings in the $SU(3)_{C}\otimes SU(3)_{L}\otimes…
We report measurements of the charge-separated $W^{+(-)} \to e^{+(-)} + \nu_e(\bar{\nu}_e)$ and $Z/\gamma^* \to e^+e^-$ production cross sections at mid-rapidity in proton-proton collisions at $\sqrt{s}$ = 500 GeV. These results are based…
In the case of the process $e^+e^-\to\mu^+\mu^-$, we study the sensitivity to either $Z^\prime$ or anomalous gauge coupling effects of two new observables, $\sigma_+$ and $\sigma_-$, conveniently defined for such kind of analysis. We…
$W$ boson pair production processes at $e^+e^-$ and $pp$ colliders have been conventionally interpreted as measurements of $WWZ$ and $WW\gamma$ triple gauge couplings (TGCs). Such interpretation is based on the assumption that new physics…
The production cross sections of $J/\psi~\eta_b$, $\Upsilon\;\eta_c$ pairs in a single boson $e^+e^-$ annihilation have been studied in a wide range of energies, which will be achieved at future $e^+e^-$ colliders. The main color singlet…
The production cross sections of charmonia, charmonium-bottomonium and bottomonia pairs in a single boson $e^+e^-$ annihilation have been studied in a wide range of energies, which will be achieved at future $e^+e^-$ colliders such as ILC…
We present calculations of cross sections for single $W^-$ and $Z$ production and $W^-W^-, W^-Z, W^-\gamma, ZZ$, and $W^+W^-$ pair production within the Standard Model at $e^-e^-$ linear colliders. We evaluate Standard-Model Higgs boson…