QCD backgrounds in charged Higgs boson searches

The search for a light charged Higgs boson at the LHC will greatly depend on how well the QCD background can be controlled, especially for the fully hadronic final state where it is expected that QCD is overwhelmingly the dominant source of background. As the QCD production cross section at the LHC is large and more importantly poorly known, specific methods to suppress and consequently predict the remaining QCD multi-jet background are required. Several methods of suppressing this QCD background and data-driven methods to estimate the remaining in the signal region are discussed for both the lepton+jets and fully hadronic final state signal channels.