Search for dissertations about: "top quark"

Showing result 16 - 20 of 26 swedish dissertations containing the words top quark.

  1. 16. Exploration of extended Higgs sectors, development of a displaced track trigger, and improvements in GRID middleware

    Author : Max Isacson; Elin Bergeås Kuutmann; Patrizia Azzi; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; BSM; Supersymmetry; Standard Model; Higgs; 2HDM; Charged Higgs; Compositeness; Pattern Matching; GRID; Fysik med inriktning mot elementarpartikelfysik; Physics with specialization in Elementary Particle Physics;

    Abstract : Two possible solutions to the Standard Model (SM) fine-tuning problem are presented in this thesis, MSSM and Compositeness. The Higgs sector of the MSSM can be tested by searching for charged Higgs bosons. Two direct searches for charged Higgs bosons decaying into a top- and bottom-quark are performed using 13.2 and 36. READ MORE

  2. 17. Measurements of luminosity and a search for dark matter in the ATLAS experiment

    Author : Patrawan Pasuwan; Sara Strandberg; Christophe Clement; Erin O'Sullivan; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; particle physics; ATLAS; luminosity; track counting; dark matter; simplified model; fysik; Physics;

    Abstract : This licentiate thesis presents contributions to the luminosity measurement from the data recorded by the ATLAS detector in 2017 using a track-counting technique, as well as a search for dark matter in the ATLAS experiment using 139 fb-1 of √s = 13 TeV pp collision data delivered by the LHC from 2015 to 2018. Track-counting luminosity measurements in low-luminosity operations are performed to study the effect of low collision rates on luminosity determination. READ MORE

  3. 18. Physics at the High-Energy Frontier : Phenomenological Studies of Charged Higgs Bosons and Cosmic Neutrino Detection

    Author : Oscar Stål; Gunnar Ingelman; Johan Rathsman; Jonathan Ellis; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; particle physics; Standard Model; beyond the Standard Model; supersymmetry; Higgs physics; charged Higgs boson; LHC; flavour physics; ultra-high-energy neutrinos; Askaryan effect; radio detection; lunar satellites; Elementary particle physics; Elementarpartikelfysik; högenergifysik; High Energy Physics;

    Abstract : The Standard Model of particle physics successfully describes present collider data. Nevertheless, theoretical and cosmological results call for its extension. A softly broken supersymmetric completion around the TeV scale solves several of the outstanding issues. Supersymmetry requires two Higgs doublets, leading to five physical Higgs states. READ MORE

  4. 19. Search for Stop Using the ATLAS Detector and Performance Analysis of the Tile Calorimeter with Muons from W Decays

    Author : Stefio Yosse Andrean; Christophe Clement; Joakim Edsjö; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; particle physics; standard model; bsm; supersymmetry; stop; calorimeter; ATLAS; fysik; Physics;

    Abstract : This thesis presents a search for the supersymmetric partner of the top quark in the final state with one lepton. The search focuses especially in the region of the parameter space where the 2-body decay dominates. The analysis is performed using LHC full Run 2 data at √s = 13 TeV as recorded by the ATLAS detector. READ MORE

  5. 20. A search for leptoquarks with the ATLAS detector and hardware tracking at the High-Luminosity LHC

    Author : Mikael Mårtensson; Richard Brenner; Anders Ryd; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Leptoquarks; Hough transform; LHC; ATLAS; HL-LHC; Particle physics; Particle tracking; Cluster finding; Trigger; Fysik med inriktning mot elementarpartikelfysik; Physics with specialization in Elementary Particle Physics;

    Abstract : This thesis presents a search for pair-production of scalar leptoquarks, decaying into third-generation particles, using proton-proton collisions delivered by the Large Hadron Collider (LHC) and recorded by the ATLAS detector. It also presents the development of a hardware track trigger for the Phase-II upgrade of the ATLAS experiment. READ MORE