Ideal τ tagging with the multivariate data-analysis toolkit TMVA

The experience on using ROOT package TMVA for multivariate data analysis is reported for a problem of τ tagging in the framework of heavy charged MSSM Higgs boson searches at the LHC. We investigate with a generator level analysis how the τ tagging could be performed in an ideal case, and hadronic τ decays separated from the hadronic jets of QCD multi-jet background present in LHC experiments. A successful separation of the Higgs signal from the background requires a rejection factor of 105 or better against the QCD background. The τ tagging efficiency and background rejection are studied with various MVA classifiers.