The top quark is the heaviest particle in the Standard Model, with a strong coupling to the Higgs boson. It is often seen as a window to new physics, therefore understanding its production is a key ingredient for testing the Standard Model or physics Beyond the Standard Model. In this document, the production cross section of top-antitop pairs in its semileptonic decay channel is measured as a function of the jet multiplicity in the ATLAS experiment, using proton-proton collisions at the center-of-mass energy of sqrt(s) = 7 TeV. The top-antitop production with extra jets is the main background for many analyses, including the top-antitop-Higgs production studies. The analysis performed is extended in a search for Beyond the Standard Model physics which predicts a resonance decaying in a top-antitop pair, using ATLAS data at center-of-mass energy of sqrt(s) = 7 TeV. The latter analysis is repeated for ATLAS data collected with sqrt(s) = 8 TeV. Performance studies of b-tagging algorithms in the ATLAS Trigger System are also presented.
Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:591994 |
Date | January 2014 |
Creators | Ferreira de Lima, Danilo Enoque |
Publisher | University of Glasgow |
Source Sets | Ethos UK |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
Source | http://theses.gla.ac.uk/5015/ |
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