Search for flavour-changing neutral current interactions in the top-quark Higgs boson sector in multi-lepton final states with the ATLAS detector at the [...] / von Oliver Thielmann. Wuppertal, Oktober 2023
Inhalt
- 1 Introduction
- 2 The Standard Model of particle physics
- 2.1 Particles and interactions
- 2.2 Electroweak theory
- 2.3 Quantum chromodynamics
- 2.4 Experimental validation
- 2.5 Limitations
- 3 Flavour-changing neutral currents
- 4 The Large Hadron Collider and the ATLAS experiment
- 5 Simulation of proton-proton collisions
- 6 Object definitions
- 6.1 Tracks and vertices
- 6.2 Electrons
- 6.3 Muons
- 6.4 Jets
- 6.5 Flavour tagging
- 6.6 Non-prompt lepton sources
- 6.7 Missing transverse momentum
- 6.8 Overlap removal
- 7 Data and simulated samples
- 7.1 Recorded data and trigger
- 7.2 Signal FCNC samples
- 7.3 Background samples
- 7.4 Building the non-prompt lepton templates
- 8 Event selection and region definition
- 9 Reconstruction
- 9.1 Neutrino weighting method
- 9.2 Reconstructed Z-boson mass
- 9.3 Neutrino-independent combinatorics estimator
- 9.4 Same-charged and opposite-charged leptons
- 9.5 Recursive jigsaw reconstruction
- 10 Multivariate analysis
- 11 Statistical analysis techniques
- 12 Systematic uncertainties
- 12.1 Experimental systematic uncertainties
- 12.2 Theoretical uncertainties
- 12.3 Implementation of systematic uncertainties
- 13 FCNC search results
- 13.1 Background-only fit
- 13.2 Realistic Asimov fit
- 13.3 Realistic Asimov fit results and exclusion limits
- 14 Conclusion and outlook
- Appendices
- A b-tagging WP study
- B Monte Carlo Samples
- C Comparison of the left- and right handed prod-FCNC processes
- D Composition of the non-prompt templates
- E Pre-fit event yields
- F Plots related to the background-only fit
- G Validation plots of kinematic distributions
- H Plots related to the realistic Asimov Fit
- Bibliography