Search for triboson $W^{\pm}W^{\pm}W^{\mp}$ production in $pp$ collisions at $\sqrt{s}=8$ TeV with the ATLAS detector

TL;DR

This study searches for triboson $W^{ ext{±}}W^{ ext{±}}W^{ ext{∓}}$ production in proton-proton collisions at 8 TeV using the ATLAS detector, finding no significant excess and setting upper limits on production cross sections and anomalous couplings.

Contribution

First search for triboson $W^{ ext{±}}W^{ ext{±}}W^{ ext{∓}}$ production at 8 TeV with ATLAS, providing new limits on cross sections and gauge couplings.

Findings

Observed event counts consistent with Standard Model predictions.

Set 95% CL upper limit on triboson production cross section at 730 fb.

Established limits on anomalous quartic gauge couplings.

Abstract

This paper reports a search for triboson $W^{\pm}W^{\pm}W^{\mp}$ production in two decay channels ($W^{\pm}W^{\pm}W^{\mp}\rightarrow \ell^{\pm}\nu\ell^{\pm}\nu\ell^{\mp}\nu$ and $W^{\pm}W^{\pm}W^{\mp}\rightarrow \ell^{\pm}\nu\ell^{\pm}\nu{}jj$ with $\ell=e, \mu$) in proton-proton collision data corresponding to an integrated luminosity of 20.3 fb$^{-1}$ at a centre-of-mass energy of 8 TeV with the ATLAS detector at the Large Hadron Collider. Events with exactly three charged leptons, or two leptons with the same electric charge in association with two jets, are selected. The total number of events observed in data is consistent with the Standard Model (SM) predictions. The observed 95 % confidence level upper limit on the SM $W^{\pm}W^{\pm}W^{\mp}$ production cross section is found to be 730 fb with an expected limit of 560 fb in the absence of SM $W^{\pm}W^{\pm}W^{\mp}$ production. Limits are also set on $WWWW$ anomalous quartic gauge couplings.