This thesis presents the measurement and results of the Z/γ* → μ⁺μ⁻ Drell-Yan triple-differential cross-section, using 20.24 fb⁻¹ of ATLAS data recorded in 2012 at a centre-of-mass energy of √s = 8TeV. The triple-differential cross-section is measured as a function of dimuon invariant mass, m_μμ, dimuon rapidity, γ_μμ , and lepton decay angle in the Collins-Soper frame, cosθ*. These dimensions provide sensitivity to the parton composition of the proton through the parton density functions, PDFs, and the weak effective mixing angle, sin²θeff./W, via the forward-backward asymmetry, A_FB. The measurement is performed on and around the Z-boson's invariant mass peak, 46 < m_μμ < 200 GeV, in a kinematic ducial volume of muon transverse momentum, pT > 20 GeV, and muon pseudo-rapidity |η|≤2.4. The results are unfolded from the detector level to the Born, bare and dressed levels, where a precision of < 0:6% is reported in the central bins. The data is combined with an electron channel measurement resulting in a combined result with reduced total uncertainty. The combined result is shown to constrain PDF uncertainties and achieve the most constrained sin²θeff./W uncertainty yet reported at the LHC.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:765852 |
| Date | January 2017 |
| Creators | Armitage, Lewis |
| Publisher | Queen Mary, University of London |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://qmro.qmul.ac.uk/xmlui/handle/123456789/24549 |
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