Study of the dijet mass spectrum in $pp \to W +$ jets events at $\sqrt{s}=7$ TeV

We report an investigation of the invariant mass spectrum of the two jets with highest transverse momentum in pp to W+2-jet and W+3-jet events to look for resonant enhancements. The data sample corresponds to an integrated luminosity of 5.0 inverse femtobarns collected with the CMS detector at sqrt(s) = 7 TeV. We find no evidence for the anomalous structure reported by the CDF Collaboration, and establish an upper limit of 5.0 pb at 95% confidence level on the production cross section for a generic Gaussian signal with mass near 150 GeV. Additionally, we exclude two theoretical models that predict a CDF-like dijet resonance near 150 GeV.