자료유형 | 학위논문 |
---|---|
서명/저자사항 | Targeting Natural Supersymmetry With Top Quarks. |
개인저자 | Herwig, T. Christian. |
단체저자명 | University of Pennsylvania. Physics and Astronomy. |
발행사항 | [S.l.]: University of Pennsylvania., 2019. |
발행사항 | Ann Arbor: ProQuest Dissertations & Theses, 2019. |
형태사항 | 306 p. |
기본자료 저록 | Dissertations Abstracts International 81-05B. Dissertation Abstract International |
ISBN | 9781088353578 |
학위논문주기 | Thesis (Ph.D.)--University of Pennsylvania, 2019. |
일반주기 |
Source: Dissertations Abstracts International, Volume: 81-05, Section: B.
Advisor: Lipeles, Elliot. |
이용제한사항 | This item must not be sold to any third party vendors. |
요약 | This thesis describes a search for natural supersymmetry via the production of light top squarks (stops) with the ATLAS experiment, using 13 TeV proton-proton collision data delivered by the Large Hadron Collider. A range of models is considered where the stop may decay to top quarks, b jets, and a variety of other supersymmetric particles. Stop masses as large as 950 GeV are excluded at 95% confidence level when decaying to a top quark and massless lightest supersymmetric particle (LSP). In scenarios where the LSP is a Higgsino, exclusions vary from 600 to 900 GeV depending on the relative stop branching fractions and Higgsino mass splitting. The impact of precision top-quark measurements on future searches is also discussed, including a measurement of quantum interference in top-quark production and measurement of the top-quark width. A differential mass distribution is measured in events with two charged leptons and two b-tagged jets that is sensitive to the interference property. The measurement is unfolded to particle level and the data are compared to state-of-the-art Monte Carlo predictions, which are found to describe the data well. A new technique is proposed to utilize this dataset to extract a value of the top-quark width, inspired by recent efforts to measure the Higgs boson width using off-shell decays. A value of 1.28 짹 0.27(exp.)짹0.15(theory) GeV is extracted from the ATLAS data, in good agreement with the standard model prediction. Finally, a new hardware tracking system is described for use in the upgraded ATLAS Trigger system for the high-luminosity run of the LHC. |
일반주제명 | Quantum physics. Particle physics. |
언어 | 영어 |
바로가기 |
: 이 자료의 원문은 한국교육학술정보원에서 제공합니다. |