Sicking, Eva: Multiplicity dependence of two-particle angular correlations in proton-proton collisions measured with ALICE at the LHC. 2012
Inhalt
- Introduction
- 1 Theoretical Background
- 1.1 The Standard Model of Particle Physics
- 1.2 Motivation for the Study of Multiple Parton Interactions
- 1.3 Signatures of Multiple Parton Interactions
- 1.3.1 Charged Particle Multiplicity Distributions
- 1.3.2 Multi-Jet Events
- 1.3.3 Growth of the Total Cross-Section
- 1.3.4 Growth of the J/ Yield
- 1.4 Models for Multiple Parton Interactions
- 1.4.1 pQCD Inspired Model
- 1.4.2 Clan Model
- 1.4.3 Independent Pair Parton Interaction Model
- 1.4.4 Quark Gluon String Model and the Dual Parton Model
- 1.5 High-Multiplicity Proton-Proton Collision
- 1.6 Simulation of Multiple Parton Interactions in Event Generators
- 1.7 Summary
- 2 The Large Hadron Collider
- 2.1 LHC Design
- 2.2 CERN Accelerator Complex
- 2.3 LHC History, Status, and Outlook
- 2.4 Experiments at the LHC
- 3 The ALICE Detector
- 3.1 Overview
- 3.2 VZERO Detector
- 3.3 Inner Tracking System
- 3.4 Time Projection Chamber
- 3.5 The ALICE Computing Tools
- 4 Data, Event, and Track Selection
- 4.1 ALICE Proton-Proton Collision Data Selection
- 4.1.1 Proton-Proton Collision Data at s = 0.9TeV
- 4.1.2 Proton-Proton Collision Data at s = 2.76TeV
- 4.1.3 Proton-Proton Collision Data at s = 7.0TeV
- 4.2 Monte Carlo Proton-Proton Collisions Data
- 4.2.1 Standard Simulations
- 4.2.2 Special Geant4 Transport Simulation
- 4.2.3 Special Therminator Event Simulation
- 4.3 Event Selection
- 4.4 Track Selection
- 4.5 Quality Assessments
- 4.5.1 Motivation
- 4.5.2 Global ALICE Quality Assurance Scheme
- 4.5.3 Central Tracking Quality Assurance Focusing on ITS and TPC
- 4.5.4 Detailed Quality Analysis of Used Data Sets
- 4.5.5 Evolution of Average Track and Event Properties
- 4.5.6 Conclusion
- 4.6 Summary
- 5 Analysis Method
- 5.1 Description of the Data Analysis Algorithm
- 5.2 Direct Correlation Observable
- 5.3 Derived Correlation Observables
- 5.4 Consideration of Biases in Two-Particle Correlations
- 5.4.1 Impact of Auto-Correlations of High-Multiplicity Jets
- 5.4.2 Impact of Decay Products of Short Lived Particles
- 5.5 Derivation of the Number of Multiple Parton Interactions
- 5.5.1 Multiple Parton Interactions in Pythia
- 5.5.2 Measurement of Number of Multiple Parton Interactions
- 5.5.3 Conclusion
- 5.6 Summary
- 6 Correction Procedure
- 6.1 Correction of Contamination From Secondary Particles
- 6.2 Track Reconstruction Efficiency Correction
- 6.3 Correction of Two-Track Effects and Detector Effects
- 6.4 Charged Particle Multiplicity Correction
- 6.4.1 Normalized and Extrapolated Correlation Matrix
- 6.4.2 Weighting Procedure using an Extrapolated Correlation Matrix
- 6.5 Vertex Reconstruction Efficiency Correction
- 6.6 Trigger Efficiency Correction
- 6.7 Additional Corrections
- 6.8 Summary
- 7 Systematic Uncertainties
- 7.1 Per-Trigger Yield Measurement based on a Fit Function
- 7.2 Non-Closure in the Monte Carlo Correction
- 7.3 Event Generator
- 7.4 Particle Transport Monte Carlo
- 7.5 Track Selection
- 7.6 Event Selection
- 7.7 Particle Composition
- 7.8 Detector Efficiency
- 7.9 Material Budget
- 7.10 Pileup Events
- 7.11 Correction of Strangeness Yields
- 7.12 Extrapolation Uncertainty of Strangeness Correction
- 7.13 Summary
- 8 Results
- 8.1 Per-Trigger Yield as a Function of
- 8.1.1 Comparison of ALICE Results to Model Predictions
- 8.1.2 Comparison of ALICE Results at Different Center-of-Mass Energies
- 8.2 Integrated Per-Trigger Yield
- 8.2.1 Comparison of ALICE Results to Model Predictions
- 8.2.2 Comparison of ALICE Results at Different Center-of-Mass Energies
- 8.2.3 Results at Different Transverse Momentum Thresholds
- 8.3 Insight into Multiple Parton Interactions
- 8.3.1 Limit in the Number of Multiple Parton Interactions
- 8.3.2 Number of Multiple Parton Interactions in ALICE Data
- 8.4 Summary
- Summary
- Zusammenfassung
- A Kinematic Variables
- B The Global Coordinate System of ALICE
- C List of Analyzed Data Sets
- D Distance of Closest Approach
- E Evolution of Track and Event Parameters
- Acknowledgements