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arXiv · 1511.07706

Improved effective vector boson approximation revisited

Werner Bernreuther·Long Chen
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Abstract

We reexamine the improved effective vector boson approximation which is based on two-vector-boson luminosities $\mathrm{\mathbf{L}}_{\rm pol}$ for the computation of weak gauge-boson hard scattering subprocesses $V_1 V_2\to {\cal W}$ in high-energy hadron-hadron or $e^-e^+$ collisions. We calculate these luminosities for the nine combinations of the transverse and longitudinal polarizations of $V_1$ and $V_2$ in the unitary and axial gauge. For these two gauge choices the quality of this approach is investigated for the reactions $e^-e^+ \to W^- W^+ ν_e {\barν}_e$ and $e^-e^+ \to t {\bar t} ν_e {\barν}_e$ using appropriate phase-space cuts.

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Werner Bernreuther, Long Chen. 2016-04-04. Improved effective vector boson approximation revisited. https://doi.org/10.1103/physrevd.93.053018

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