Four Fermion processes at LEP II

TL;DR

This paper reports on the first measurements of four fermion processes at LEP II, including $WW$, $We u$, $ZZ$, and $Z\gamma^ ext{*}$ production, confirming Standard Model predictions with new experimental data.

Contribution

It provides the first experimental measurements of multiple four fermion processes at LEP II, including cross sections, branching fractions, and limits on anomalous couplings.

Findings

Measured $WW$ cross section and W branching fractions.

Set limits on $ZZZ$ and $ZZ\gamma$ anomalous couplings.

Results agree with Standard Model expectations.

Abstract

In its second phase, LEP has given the unique opportunity to study four fermion processes never observed before. This papers deals with a preliminary study of $WW$, $We\nu$, $ZZ$ and $Z\gamma^\star$ production in $e^+e^-$ collisions. Measurement results on $WW$ cross section, $W$ branching fractions, $WWV$ ($V=Z/\gamma$) anomalous couplings and $W$ average polarization in $WW$ events are presented. Moreover cross section measurements for $We\nu$, $ZZ$ and $Z\gamma^\star$ production and limits on $ZZZ$ and $ZZ\gamma$ anomalous couplings are reported. All the results are in good agreement with the Standard Model expectations.