Combination of Run-1 Exotic Searches in Diboson Final States at the LHC

TL;DR

This paper combines ATLAS and CMS results from 8 TeV LHC data to search for heavy resonances decaying into diboson final states, setting limits and identifying the most consistent mass range for potential new physics signals.

Contribution

It provides the first combined analysis of multiple diboson searches from ATLAS and CMS at 8 TeV, interpreting results within specific new physics models.

Findings

Heavy resonance with cross section 4-5 fb around 1.9-2.0 TeV is most consistent with data.

Models favoring decay to WW are disfavoured.

Combined analysis improves sensitivity over individual searches.

Abstract

We perform a statistical combination of the ATLAS and CMS results for the search of a heavy resonance decaying to a pair of vector bosons with the $\sqrt{s}=8$ TeV datasets collected at the LHC. We take into account six searches in hadronic and semileptonic final states carried out by the two collaborations. We consider only public information provided by ATLAS and CMS in the HEPDATA database and in papers published in refereed journals. We interpret the combined results within the context of a few benchmark new physics models, such as models predicting the existence of a {\ensuremath{\mathrm{W^\prime}}\xspace} or a bulk Randall-Sundrum spin--2 resonance, for which we present exclusion limits, significances, $p$-values and best-fit cross sections. A heavy diboson resonance with a production cross section of $\sim$4-5 fb and mass between 1.9 and 2.0 TeV is the exotic scenario most consistent with the experimental results. Models in which a heavy resonance decays preferentially to a WW final state are disfavoured.