Prospects of a cross section ratio measurement of W and Z events as a function of the jet multiplicity with early ATLAS data / von Marisa Sandhoff. 2010
Content
- Introduction
- Physical context
- LHC and ATLAS
- Particle accelerators and collision experiments
- Short overview of recent experiments in high energy physics
- Large Hadron Collider (LHC)
- ATLAS Experiment
- Object identification and reconstruction
- Tracks
- Electrons and photons
- Jets
- Muons
- -leptons
- Neutrinos (missing transverse energy)
- Data simulation
- Jet algorithms
- ATLAS jet algorithms
- Event selection
- Matching of quark - particle jet - calorimeter jet
- Jet energy
- Effects from both fragmentation and measurement
- Effects from fragmentation and measurement separately
- Angular resolution
- Influence of pile up on energy resolution
- b-tagging
- Summary
- Motivation of measuring W+jets/Z+jets
- W and Z event shapes
- Event selection
- Expected differences in W and Z events
- Similarities of W and Z events
- Z+jets to estimate W+jets
- Summary
- Ratio W+jets/Z+jets
- Strategy of the measurement
- Data samples
- Event selection
- Trigger
- Selection of W and Z events
- W and Z event selection results
- Jet definition and selection
- W+jets and Z+jets event selection results
- Nomenclature
- Background subtraction
- Ratio measurement
- Systematic uncertainties
- Jet energy scale and resolution
- Electron energy scale and resolution
- E-.1ex/T energy scale and resolution
- Background estimate
- QCD background estimate
- W -3.45mu Z migrations
- Combined systematic uncertainty
- Results
- Unfolded ratio W+jets/Z+jets
- Correcting detector effects
- Migrations of events
- Reversing the migrations: Unfolding
- Unfolding based on Bayes` Theorem
- Testing the unfolding method
- Model dependence of the migration matrix
- Summary
- Strategy of the measurement
- Statistical unfolded results
- Pseudo experiments
- Final statistical results
- Systematic uncertainties
- Signal efficiency
- Results
- Summary and Outlook
- References