H->tau tau and H->tau nu with the ATLAS Detector at the LHC

The discovery and study of the source of electroweak symmetry breaking, usually explained through the Higgs mechanism, is one of the main goals of the ATLAS experiment, operating at the Large Hadron Collider (LHC). This mechanism predicts the existence of one or more scalar particles, the Higgs bosons. Channels containing taus are very important for the Higgs boson search at the LHC. Within the Standard Model, the H->tau tau channel would provide a significant contribution to the Higgs boson search in the dicult region of low Higgs mass. This channel is also important in supersymmetric extensions of the Standard Model through the associated production of the Higgs bosons with heavy quarks or by gluon fusion. Finally, the observation of a charged Higgs boson would constitute irrefutable evidence for physics beyond the Standard Model. A light enough charged Higgs would be produced in top quark decays through t ! bH+ and would likely decay to a tau lepton and a neutrino. This paper summarizes recent ATLAS studies focusing on the above channels, and concentrates on several experimental aspects of these analyses.