Searches for heavy diboson resonances in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

TL;DR

This paper reports on searches for heavy diboson resonances in proton-proton collisions at 13 TeV using the ATLAS detector, setting new limits on various theoretical models and extending previous mass exclusion ranges.

Contribution

First comprehensive search for heavy diboson resonances at 13 TeV with combined analysis of multiple final states, providing the most stringent limits to date.

Findings

No significant deviations from the Standard Model.

Excluded scalar singlet masses below 2650 GeV.

Excluded heavy vector-boson triplet masses below 2600 GeV.

Abstract

Searches for new heavy resonances decaying to $WW$, $WZ$, and $ZZ$ bosons are presented, using a data sample corresponding to 3.2 fb$^{-1}$ of $pp$ collisions at $\sqrt{s}=13$ TeV collected with the ATLAS detector at the CERN Large Hadron Collider. Analyses selecting $\nu\nu qq$, $\ell\nu qq$, $\ell\ell qq$ and $qqqq$ final states are combined, searching for a narrow-width resonance with mass between 500 and 3000 GeV. The discriminating variable is either an invariant mass or a transverse mass. No significant deviations from the Standard Model predictions are observed. Three benchmark models are tested: a model predicting the existence of a new heavy scalar singlet, a simplified model predicting a heavy vector-boson triplet, and a bulk Randall-Sundrum model with a heavy spin-2 graviton. Cross-section limits are set at the 95% confidence level and are compared to theoretical cross-section predictions for a variety of models. The data exclude a scalar singlet with mass below 2650 GeV, a heavy vector-boson triplet with mass below 2600 GeV, and a graviton with mass below 1100 GeV. These results significantly extend the previous limits set using $pp$ collisions at $\sqrt{s}=8$ TeV.