Goussiou, AnnaKeller, John Stakely2013-11-142013-11-142013-11-142013Keller_washington_0250E_12332.pdfhttp://hdl.handle.net/1773/24311Thesis (Ph.D.)--University of Washington, 2013A search for the neutral Higgs bosons of the Minimal Supersymmetric Standard Model (MSSM), produced in proton-proton collisions recorded by the ATLAS detector, is pre- sented. The data correspond to an integrated luminosity of 20.3 fb<super>-</super> , with a center of mass energy of 8 TeV. The search focuses on final states where the Higgs bosons decay into a &tau<super>+</super> &tau<super>-</super> pair, with one &tau lepton decaying leptonically and the other hadronically. Two analyses are performed which separately target low-mass and high-mass Higgs bosons, with the former divided into two sub-channels based on the presence or absence of a b-jet in final state. No evidence of new Higgs bosons is found, and upper limits are set on the cross-section times branching ratio of such Higgs bosons, and on the MSSM parameters m_A and tan&beta.application/pdfen-USCopyright is held by the individual authors.PhysicsphysicsThesis