Study of heavy MSSM-Higgs bosons A/H in hadronic tau-decays in ATLAS

The discovery potential of the ATLAS experiment for the Higgs bosons postulated in the Minimal Supersymmetric extension to the Standard Model (MSSM) can be extended to regions of large masses and large tanbeta > 40 by studying the tau decay channel. In the present note the search for A/H decays into tau pairs has been studied in the hadronic decay mode of both tau's for large masses (m(A/H) > 500 GeV). Due to the small production cross section for large masses and the high rates from QCD background and the absence of a trigger lepton, the first level trigger performance is of crucial importance. A study has been performed to estimate the signal acceptance and trigger rates. A high signal acceptance in the first level trigger can be achieved using standard trigger conditions, while retaining suitable trigger rates. The study of signal and backgrounds shows that MSSM-Higgs bosons A/H can be discovered at ATLAS assuming an integrated luminosity of 30 fb-1 for masses of m(A/H) = 600 GeV for tanbeta > 50, and for masses of m(A/H) = 800 GeV for tanbeta > 75. All results are for the low luminosity case.