Precision tests of EWK sector and direct searches for new physics with di-boson production

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The initial focus of this project is to search for new physics resonances in the electroweak (EWK) sector using data collected fromATLAS at the LHC. The searches are looking for particles such as the Randell-Sundrum Graviton, G, and the heavy vector boson W0.The decay channels investigated in this project are ZZ or WZ llqq, where W and Z are the charged and neutral vector bosons l is a leptonand q is a quark. The lepton is either an electron or a muon and the quarks form jets which can be resolved as either two jets or one largejet depending on the momentum of the quarks. An important part of these searches are the modeling of the background events and any sys-tematics associated with the analysis. If no new physics is found then limits will be placed on the production rate for hypothetical signals.The project will also set limits on the anomalous Triple Gauge Boson Couplings (aTGC), e.g. WW Z, and anomalous Quartic Gauge Bo-son couplings (aQGC), e.g. WZ X WZ. This is done using the effective Lagrangian approach which investigates the contributions ofloop and off-shell processes to lower energy levels which are achievable at the LHC. The investigations into this look at the kinematic distri-butions of the WW or WZ to see if there are any signicant changes due these processes.The authorship task for ATLAS associated with this project is the investigation into the observed innefficiency of the muon trigger full scanchains in the case of close by muons. The full scan procedure is an event filter process which searches the whole detector without usingany information from the other levels of the trigger. The observed innefficiency is 10% per muon when muons are close each other atdR < 0:3. The aim of the task is to investigate the problem, its causes and to find a solution to increase the innefficiency.