Search for a W' boson decaying to a muon and a neutrino in pp collisions at sqrt(s) = 7 TeV

Abstract

A new heavy gauge boson, W', decaying to a muon and a neutrino, is searched for in pp collisions at a centre-of-mass of 7 TeV. The data, collected with the CMS detector at the LHC, correspond to an integrated luminosity of 36 inverse picobarns. No significant excess of events above the standard model expectation is found in the transverse mass distribution of the muon-neutrino system. Masses below 1.40 TeV are excluded at the 95% confidence level for a sequential standard-model-like W'. The W' mass lower limit increases to 1.58 TeV when the present analysis is combined with the CMS result for the electron channel.

Figures (3)

• Figure 1: The $M_\mathrm{T}$ distribution after all the selection steps, in the data and in the simulation. A $\mathrm{W'}$ signal with two different hypothetical masses is shown.
• Figure 2: Display of the highest-$M_\mathrm{T}$ event in transverse view (left) and longitudinal view (right). The four barrel muon stations are shown in red, the forward muon stations in blue. Charged particle tracks as well as the deposited energy per calorimeter cell are displayed. The muon with $p_{\mathrm{T}}$=249$\,\text{Ge\spaceV}$ is symbolized by a red line moving upward, and the $E_{\mathrm{T}}^{\text{miss}}$=238.6$\,\text{Ge\spaceV}$ ("pfMet") by a blue line moving downward.
• Figure 3: Individual limits as observed for the electron (black line) and the muon channel (red line). Their combination is shown as a solid blue line for the observed limit (expected as dashed blue line), using a Bayesian technique with only the luminosity uncertainty correlated.