相关论文: Light Fermion Mass Effects in e^+e^- -> 4 Fermions
The fermion mass effects in e+ e- --> 4f and in the corresponding bremsstrahlung reactions in the presence of realistic cuts are studied. It is shown that, for some four--fermion final states, the mass effects become sizeable to the extent…
An improved efficient method of calculating the hard bremsstrahlung correction to e^+ e^- -> 4f for non-zero fermion masses is presented. The non-vanishing fermion masses allow us to perform the phase space integrations to the very…
We review the results on representing the differential cross section for W-pair produciton, including W decay and hard-photon bremsstrahlung, in terms of a Born-form approximation of fairly simple analytic form. The result of the Born-form…
A recently suggested high-energy Born-form representation of the one-loop helicity amplitudes for e^+e^- to W^+W^- is supplemented by including W^+- decay and hard-photon radiation. Results for the differential and the total cross section…
Possible oblique effects from vector particles that are strongly coupled to the known gauge bosons are calculated for the case of final hadronic states produced at future $e^+e^-$ colliders, using a formalism that was recently proposed and…
The production of four fermions plus a visible photon in electron-positron collisions is analyzed, with particular emphasis on the LEP2 energy range. The study is based on the calculation of exact matrix elements, including the effect of…
For energies relevant to future linear colliders, \sqrt{s} >~ 500 GeV, the WW fusion channel dominates the Higgs boson production cross section e+e- -> \bar\nu \nu h^0. We have calculated the one-loop corrections to this process due to…
The relevance of fermion loop corrections to four fermion processes at e+ e- colliders is reviewed with regard to the recent extension to the case of massive external particles and its application to single-W processes.
We accomplish our efforts to obtain predictions for all four-fermion final states of e+ e- annihilation and the corresponding bremsstrahlung reactions which are possible in the framework of the Standard Model. For this purpose we have…
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…
The cross sections for the reaction $e^+ e^- \rightarrow l \bar l q \bar q $ and for similar four fermion production processes at LEP~1, LEP~2 and the NLC are calculated. Due to the extraordinary symmetry properties of the process, very…
For energies relevant to future linear colliders, $\sqrt{s} \gsim 500$ GeV, the WW fusion channel dominates the Higgs boson production cross section $e^+ e^- \to \bar{\nu} \nu h^0$. We have calculated the one-loop corrections to this…
In the energy region of LEP2 and above, four fermion final states in e+e- collisions can be produced by Feynman diagrams involving two, one or zero resonant bosons...
The change in orientation in generation space (rotation) of the fermion mass matrix with changing scales can lead to flavour-violations through just the kinematics of a non-diagonal mass matrix. Such effects for the reactions: $e^+ e^-…
We present results for the light, strange and charm quark masses using $N_f=2+1+1$ twisted mass fermion ensembles at three values of the lattice spacing, including two ensembles simulated with the physical value of the pion mass. The…
Top and bottom one loop corrections to $e^+e^-\rightarrow H^+ H^-$ are considered at NLC energies and found to be significantly large and negative over the full range of $tan \, \beta$. Moreover, loop effects of moderately heavy squarks and…
The next generation of high energy e+ e- linear colliders is expected to operate at \sqrt{s} \gtsim 500 GeV. In this energy range the WW fusion channel dominates the Higgs boson production cross section e+ e- -> \bar\nu \nu h^0/H^0. We…
We report measurements of production cross sections for $\rho^+$, $\rho^0$, $\omega$, $K^{*+}$, $K^{*0}$, $\phi$, $\eta$, $K_S^0$, $f_0(980)$, $D^+$, $D^0$, $D_s^+$, $D^{*+}$, $D^{*0}$, and $D^{*+}_s$ in $e^+e^-$ collisions at a…
We consider the effects of a light quark mass in the soft-collinear effective theory (SCET) and we apply them to B -> X_s gamma in the endpoint region. We find that the reparameterization invariance can be extended by including the…
In the recent past,unparticle physics effects have been explored in detail in both the fermionic and bosonic sectors. We have used fermionic unparticles to study the cross-section of electron-positron annihilation to light pseudo-scalar…