A multi-dimensional search for new heavy resonances decaying to boosted W W , W Z , or Z Z boson pairs in the dijet final state at 13 Te

Abstract

A search in an all-jet final state for new massive resonances decaying to $\text{W}$ $\text{W}$ , $\text{W}$ $\text{Z}$ , or $\text{Z}$ $\text{Z}$ boson pairs using a novel analysis method is presented. The analysis is performed on data corresponding to an integrated luminosity of 77.3 ${\text{fb}}^{-1}$ recorded with the CMS experiment at the LHC at a centre-of-mass energy of 13 $\text{Te}$ . The search is focussed on potential narrow-width resonances with masses above 1.2 $\text{Te}$ , where the decay products of each $\text{W}$ or $\text{Z}$ boson are expected to be collimated into a single, large-radius jet. The signal is extracted using a three-dimensional maximum likelihood fit of the two jet masses and the dijet invariant mass, yielding an improvement in sensitivity of up to 30% relative to previous search methods. No excess is observed above the estimated standard model background. In a heavy vector triplet model, spin-1 ${\text{Z}}^{\text{'}}$ and ${\text{W}}^{\text{'}}$ resonances with masses below 3.5 and 3.8 $\text{Te}$ , respectively, are excluded at 95% confidence level. In a bulk graviton model, upper limits on cross sections are set between 27 and 0.2 $\text{fb}$ for resonance masses between 1.2 and 5.2 $\text{Te}$ , respectively. The limits presented in this paper are the best to date in the dijet final state.

Keywords: CMS; Diboson resonances; Physics; Substructure.