Search for neutral MSSM Higgs bosons decaying to τhadτhad in √(s)=7 TeV proton-proton collisions with the ATLAS detector

In this thesis a search for the neutral Higgs bosons of the Minimal Supersymmetric Standard Model (MSSM) in the h/A/H→τhadτhad decay channel is described. The analysis is based on a sample of proton-proton collisions at a centre-of-mass energy of 7 TeV recorded with the ATLAS detector at the Large Hadron Collider. The data were recorded in 2011 and correspond to an integrated luminosity of 4.7 fb-1. Final states with two hadronic tau-lepton decays requiring either the presence or absence of b-jets are considered and the selection is optimised for Higgs bosons in b-quark associated and gluon-fusion production. No statistically significant excess over the expected background is observed and exclusion limits at the 95% confidence level are derived in combination with the h/A/H→μμ, h/A/H→τeτμ and h/A/H→τlepτhad decay channels. The exclusion limits are shown for the production cross section of a generic neutral Higgs boson, φ, as a function of the Higgs boson mass and for h/H/A production in the MSSM as a function of the parameters mA and tan(β) in the mh-max scenario.