Measurement of the double-differential W -> µν cross-section at high transverse masses at √s= 13 TeV with the ATLAS detector / Johanna Wanda Kraus. Wuppertal, October 2024
Content
- Introduction
- 1 Theoretical and experimental context
- 1.1 The Standard Model of Elementary Particle Physics
- 1.1.1 Overview of fundamental particles and interactions
- 1.1.2 The strong interaction
- 1.1.3 The electroweak interaction
- 1.1.4 The Higgs mechanism
- 1.1.5 Predictions with the Standard Model
- 1.1.6 Experimental validation and limitations of the SM
- 1.2 W-boson production in proton-proton collisions
- 1.2.1 Physics of proton-proton collisions in a nutshell
- 1.2.2 Parton distribution functions
- 1.2.3 The charged-current Drell-Yan process at high transverse masses
- 1.3 Motivation and interpretation opportunities
- 2 The ATLAS experiment at the Large Hadron Collider
- 3 Data and simulated samples
- 4 Particle identification and reconstruction
- 4.1 ID tracks and vertices
- 4.2 Muons
- 4.2.1 Reconstruction
- 4.2.2 Identification
- 4.2.3 Isolation
- 4.2.4 Momentum scale and resolution corrections
- 4.2.5 Sagitta bias correction
- 4.2.6 Efficiency corrections
- 4.2.7 Summary of the muon selection
- 4.3 Electrons
- 4.4 Jets
- 4.5 Missing transverse momentum
- 4.6 Overlap removal
- 5 Event selection and measurement binning
- 6 Estimation of the multijet background
- 6.1 Matrix Method
- 6.2 Measurement of the real efficiency
- 6.3 Study of fake-muon kinematics using a dijet MC sample
- 6.4 Measurement of the fake efficiency
- 6.5 Systematic uncertainties on the multijet background
- 6.6 Multijet closure and validation regions
- 7 Comparison between data and prediction in the signal region
- 7.1 Composition of signal and background
- 7.2 Distributions of control variables
- 7.3 Measurement observables
- 8 Unfolding of the differential cross-sections
- 8.1 The unfolding problem
- 8.2 Cross-section measurement
- 8.2.1 Theoretical formulation of Iterative Bayesian Unfolding
- 8.2.2 Response matrix
- 8.2.3 Efficiency and in-smearing corrections
- 8.2.4 Usage of a shadow bin
- 8.2.5 Optimization of the number of iterations
- 8.3 Tests of the unfolding procedure
- 8.3.1 Technical closure test
- 8.3.2 Data-driven closure test
- 8.3.3 Unfolding of alternative signal prediction
- 8.4 Procedure of unfolding uncertainties
- 9 Measurement uncertainties
- 9.1 Statistical uncertainty
- 9.2 Pre-processing of systematic uncertainties
- 9.3 Experimental systematic uncertainties
- 9.3.1 Muon uncertainties
- 9.3.2 Uncertainties on the ETmiss soft-track term
- 9.3.3 Jet uncertainties
- 9.3.4 Multijet uncertainties
- 9.3.5 Other experimental uncertainties
- 9.4 Theoretical systematic uncertainties
- 9.4.1 Signal process
- 9.4.2 tsiunitxunit-deprecatedࡡ爀戀愀爀戀愀爀琀 瀀爀漀挀攀猀
- 9.4.3 Interference between tW and tsiunitxunit-deprecatedࡡ爀戀愀爀戀愀爀琀 瀀爀漀挀攀猀猀攀
- 9.4.4 Rate uncertainty on small background processes
- 9.5 Summary
- 10 Measurement results
- 10.1 Single-differential cross-sections in mTW
- 10.2 Double-differential cross-sections in mTW ⊗|η(µ)|
- 10.3 Charge asymmetry
- 11 Combination with parallel electron-channel measurement
- Conclusion
- A Various supplemental material
- B Sagitta bias correction
- C Multijet background: supplemental material
- C.1 Real and fake efficiencies
- C.2 Fake-muon study using a dijet MC sample
- C.3 Multijet closure and validation regions
- D More distributions compared for data and prediction
- E Unfolding: supplemental material
- E.1 Binning optimization: migration and data statistical uncertainty
- E.2 Unfolding corrections for positive muon charge
- E.3 Unfolding in |η(µ)|
- E.4 Shadow bin including the W-boson mass peak
- E.5 Optimization of the number of iterations in the IBU
- E.6 Closure test and data-driven closure test
- E.7 Comparisons between Sherpa and Powheg+Pythia signal MC samples
- E.8 Hidden variables test: reweighting in pT (W)
- E.9 Smoothing of unfolding uncertainties
- E.10 Unfolding of experimental systematic uncertainties
- F Systematic uncertainties: supplemental material
- F.1 Statistical uncertainty
- F.2 Systematic uncertainties before the unfolding
- F.2.1 Experimental systematic uncertainties with respect to the signal prediction including the shadow bin
- F.2.2 Theory systematic uncertainties with respect to the top-quark background prediction
- F.2.3 Multijet systematic uncertainties with respect to the multijet yield
- F.3 Uncertainties on the unfolded W+ cross-section
- F.4 Signal theory systematic uncertainties
- F.5 Statistical fluctuations induced by the peak signal MC sample
- F.6 Small uncertainties
- G Wpm combined cross-sections
- Bibliography