Related papers: Complete Initial State QED Corrections to Off-Shel…
The precise investigation of the $W^+ W^-Z^0$ production at the $e^+e^-$ International Linear Collider(ILC) is of crucial importance in probing the couplings between massive vector gauge bosons and discovering the signature of new physics…
We give a short review of the results for four fermion production, which have been obtained by the semi-analytical approach. The angular degrees of freedom (typically five or more) are integrated over analytically while the integrations…
We briefly present the status of QCD corrections to the inclusive total cross section for the production of a Higgs boson in association with a top-quark pair within the Standard Model at hadron colliders.
A study of Z boson pair production in e+e- annihilation using the OPAL detector at LEP is reported. The ZZ production cross-section is measured, limits on anomalous ZZgamma and ZZZ couplings are derived, and constraints on models of low…
In view of the forthcoming experiments at high energy $e^+ e^-$ colliders, LEP2 and beyond, the process $e^+ e^- \to W^+ W^- \to 4f$ has been investigated for {\it off-shell} $W$'s. After deriving the matrix element for the process within…
Four-fermion productions measured in the LEP2 data are reviewed. The total and differential cross-section yields represent the first clear evidence for the existence of gauge boson self couplings, in support of the non-abelian SU(2)xU(1)…
The process e+e- --> W+W- provides a valuable laboratory to test the Standard Model (SM) and to search for new physics. The most general helicity amplitudes for this process require the introduction of nine form-factors which we calculate…
We describe the gauge-invariant treatment of the finite-width effects of W and Z bosons in the fermion-loop scheme and its application to the six-fermion (LEP2) processes e^- e^+ -> four fermions, with massless external fermions. The…
Complete electroweak two-loop corrections to the process $gg \to H$ are presented and discussed in a Standard Model with a fourth generation of heavy fermions. The latter is studied at the LHC to put exclusion limits on a fourth generation…
We compute QCD radiative corrections to the continuum production of a pair of Z-bosons in the annihilation of two gluons. We only consider the contribution of the top quark loops and we treat them assuming that $m_t$ is much larger than any…
The quartic gauge boson couplings that identify the strengths of the gauge boson self-interactions are exactly determined by the non-Abelian gauge nature of the Standard Model. The examination of these couplings at $ep$ collisions with high…
The BaBar Collaboration has an intensive program studying the cross sections of hadron production in low-energy e+e- annihilation, accessible via initial-state radiation. Our measurements allow a significant improvement in the precision of…
We present a complete calculation of the electroweak O(alpha^3 alpha_s) corrections to three-jet production and related event-shape observables at electron--positron colliders. The Z-boson resonance is described within the complex-mass…
Radiative corrections to processes that involve the production and subsequent decay of unstable particles are complex due to various theoretical and practical problems. The so-called double-pole approximation offers a way out of these…
Some of the most interesting Higgs-production processes at future e+ e- colliders are of the type e+ e- -> f anti-f H. We present a calculation of the complete O(alpha) corrections to these processes in the Standard Model for final-state…
We study the Initial state radiation (ISR) process, $e^- e^+ \rightarrow^*\gamma\rightarrow \gamma +J/\psi$ observed at high luminosity $e^- e^+$ colliders such as B-factories, with the ISR photon being emitted through the initial electron…
For the first time the experiments ALEPH, DELPHI, L3 and OPAL have presented preliminary results for fermion-pair and photon-pair production in e+e- collisions on the full LEP2 data set. The details of the experimental measurements and…
Cross-sections for hadronic, b-bbar and lepton pair final states in e+e- collisions at sqrt(s) = 183 GeV, measured with the OPAL detector at LEP, are presented and compared with the predictions of the Standard Model. Forward-backward…
Triboson processes allow for a measurement of the triple and quartic couplings of the Standard Model gauge bosons, which can be used to constrain anomalous gauge couplings. In this paper we calculate the next-to-leading order electroweak…
In reactions with $q \bar q$ production or $q\bar q$ annihilation, initial- and final-state interactions give rise to large corrections to the lowest-order cross sections. We evaluate the correction factor first for low relative kinetic…