Search for exotic resonances decaying into WZ/ZZ in pp collisions at sqrt(s) = 7 TeV

TL;DR

This paper reports a search for new exotic particles decaying into WZ or ZZ final states in proton-proton collisions at 7 TeV, setting limits on various theoretical models and excluding certain mass ranges.

Contribution

It presents the first search for VZ resonances in overlapping jet final states at the LHC, providing new exclusion limits on W' and graviton resonances.

Findings

No significant excess observed over background.

Excluded W' bosons with masses 700-940 GeV.

Excluded graviton resonances with masses 750-880 GeV.

Abstract

A search for new exotic particles decaying to the VZ final state is performed, where V is either a W or a Z boson decaying into two overlapping jets and the Z decays into a pair of electrons, muons or neutrinos. The analysis uses a data sample of pp collisions corresponding to an integrated luminosity of 5 inverse femtobarns collected by the CMS experiment at the LHC at sqrt(s) = 7 TeV in 2011. No significant excess is observed in the mass distribution of the VZ candidates compared with the background expectation from standard model processes. Model-dependent upper limits at the 95% confidence level are set on the product of the cross section times the branching fraction of hypothetical particles decaying to the VZ final state as a function of mass. Sequential standard model W' bosons with masses between 700 and 940 GeV are excluded. In the Randall-Sundrum model for graviton resonances with a coupling parameter of 0.05, masses between 750 and 880 GeV are also excluded.