We have measured the $\mathrm{ZZ}\ensuremath{\gamma}$ and $Z\ensuremath{\gamma}\ensuremath{\gamma}$ couplings by studying $13.1{\mathrm{pb}}^{\ensuremath{-}1}$ of $p\overline{p}\ensuremath{\rightarrow}{E}_{t}\ensuremath{\gamma}+X$ data at $\sqrt{s}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1.8\mathrm{TeV}$ with the D\O{} detector at the Fermilab Tevatron Collider. This is the first study of hadronic $Z\ensuremath{\gamma}$ production in the neutrino decay channel. Combining this measurement with our previous results using $Z\ensuremath{\rightarrow}\mathrm{ee}$ and $\ensuremath{\mu}\ensuremath{\mu}$ yields the most stringent 95% C.L. limits to date on anomalous couplings: $|{h}_{30}^{Z}|<0.4$, $|{h}_{40}^{Z}|<0.06$ ( $\ensuremath{\Lambda}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}750\mathrm{GeV}$).
Tópico:
Particle physics theoretical and experimental studies