Thesis (M.S.)--University of Michigan, 1966.

Thesis (Ph. D.)--Florida State University, 2002. / Advisor: Dr. Horst Wahl, Florida State University, College of Arts and Sciences, Dept. of Physics. Title and description from dissertation home page (Oct. 6, 2003). Includes bibliographical references.

Thesis (Ph. D.)--University of Washington, 1997. / Vita. Includes bibliographical references (p. [107]-111).

A search for the production of three massive vector bosons with at least one Z boson is presented. 140 fb⁻¹ of pp collisions at center-of-mass energy sqrt(s) = 13 TeV collected with the ATLAS detector at the LHC from 2015 to 2018 are analyzed. Events with three leptons and at least one reconstructed jet are discussed, targeting the WWZ → lνqqll and WZZ → lνqqll decay channels. Evidence for the searched-for production process is observed. Additional results demonstrating the combination of the three lepton search with searches including four or more leptons are shown. Pending the unblinding and combination of these results, there is potential for the discovery of the searched-for production process.

Measurements of the jet substructure in Pb+Pb collisions provide information about the mechanism of jet quenching in the hot and dense QCD medium created in these collisions, over a wide range of energy scales. Recent measurements of the nuclear modification factor of large-radius jets in 5.02 TeV Pb+Pb collisions with ATLAS are presented. 2017 pp data of 257 inverse picobarns and 2018 Pb+Pb data of 1.72 inverse nanobarns are used in these measurements. The R=1.0 large-radius jets are reconstructed with the anti-kt algorithm from R=0.2 anti-kt jets. In each large-radius jet, the associated R=0.2 jets, as constituents, are re-clustered using the kt algorithm to obtain the earliest splitting substructure observables, including the splitting scale sqrt(d12) and the angular separation dR. The nuclear modification factor RAA, which is the jet yield suppression in Pb+Pb compared to pp, is measured as a function of the jet transverse momentum pt and jet substructure observables sqrt(d12) and dR. A significant RAA decrease for jets with one single sub-jet is observed, compared to jets with more complex substructure. These results support the hypothesis that jets with hard internal splittings losemore energy propagating through the medium. Measurements of RAA with dependence on the jet substructure characterized using charged particle fragments are also presented. Utilizing jets of a consistent definition, the substructure observables, specifically the splitting scale sqrt(d12) and the angular separation dR, are extracted from the kt re-clusterings of charged particles associated to each large-radius jet. The soft-drop grooming algorithm is applied with the kt re-clusterings of the charged particles to mitigate the strong underlying event effects. RAA is found to have a significant decrease with increasing sqrt(d12) and dR at their lower values, suggesting possible color coherence effects influencing the jet energy loss in the medium.

This PhD thesis presents the measurement of the differential cross section for the production of a Z boson in association with jets in proton-proton collisions taking place at the Large Hadron Collider (LHC) at CERN, at a centre-of-mass energy of 8 TeV. A development of a data acquisition (DAQ) system for the Triple-Gas Electron Multiplier (GEM) detector in view of the Compact Muon Solenoid (CMS) detector upgrade is also presented.<p><p>The events used for the data analysis were collected by the CMS detector during the year 2012 and constitute a sample of 19:6 fb-& / Doctorat en Sciences / info:eu-repo/semantics/nonPublished