Top CSC Notes Figures

The ATLAS CSC book was published online at the end of 2008 as CERN-OPEN-2008-20 or hep-ex arXiv:0901.0512. The figures from the Top Chapter CSC notes can be found below.

Top Chapter Introduction (T0)

• Figure 1 - Top-pair production at lowest order
• Figure 2 - Three production mechanisms for single top

Top Trigger (T5)

• Figure 1a and Figure 1b Electron trigger efficiency on W events
• Figure 2a and Figure 2b Muon trigger efficiency on W events
• Figure 3a and Figure 3b and [Figure 3c Muon trigger efficiency on ttbar events
• Figure 4a and Figure 4b and [Figure 4c Jet trigger efficiency on hadronic ttbar events
• Figure 5 Etmiss spectra for hadronic ttbar events in the LVL1 trigger
• Figure 6 Lepton triggers on single top events
• Figure 7 Trigger item overlaps
• Figure 8a, Figure 8b, Figure 8c , Figure 8d Effect of trigger on reconstructed quantities

Top Light Jets (T2)

• Figure 1 Distributions of (Equark - Ejet )/Equark for the jets from the W-boson decay
• Figure 2 Energy resolution for jets from light quarks
• Figure 3 Comparison of the jet energy resolutions with respect to the Monte Carlo hadrons
• Figure 4 Comparison of the jet energy resolutions for events simulated with and without pile-up
• Figure 5 Relative difference between the Monte Carlo jet energy and the reconstructed jet energy
• Figure 6 Relative difference between the quark energy and the Monte Carlo jet energy
• Figure 7 Relative difference between the quark and the jet energy with and without pileup
• Figure 8 Distance between the jet and the quark
• Figure 9 Resolution on the distance between the jet and the quark
• Figure 10 Invariant di-jet mass as an estimate of the hadronically decaying W-boson mass
• Figure 11 Invariant mass mjj of the selected jet-jet pairs
• Figure 12 The apparent jet energy scale due to a cut on the transverse momenta
• Figure 13 Shift of the reconstructed W boson mass
• Figure 14 Shift of the reconstructed top mass
• Figure 15 Ejet/Equark for jets originating from a W-boson
• Figure 16 (1-cos(theta jjMC ))/(1-cos(theta jj)) as function of the reconstructed cos(theta jj)
• Figure 17 Result of the iterative rescaling method as a function of E jet , with 10 fb-1
• Figure 18 Result of the iterative rescaling method as a function of eta jet , with 10 fb-1
• Figure 19 Result of the iterative rescaling method as a function of E jet , with 1 fb-1
• Figure 20 Result of the iterative rescaling method as a function of eta jet , with 1 fb-1
• Figure 21 Jet-jet invariant mass in fully simulated events superimposed on the best template histogram
• Figure 22 Fitted jet energy scale as a function of the top mass
• Figure 23 Fitted jet energy scale for sixteen 48 pb-1 pseudo-experiments
• Figure 24 Reconstructed W-boson mass distribution in datasets with different gluon radiation settings
• Figure 25 pT distribution of the jets from the hadronic W-boson decay for datasets with different gluon radiation settings
• Figure 26 Total number of reconstructed jets with pT > 10 GeV for datasets with different gluon radiation settings
• Figure 27 pT of the additional jets for datasets with different gluon radiation settings

Top Cross Section (T6)

Single lepton Commissioning analysis:

• Figure1_left: Three-jet invariant mass distribution for the electron analysis
• Figure1_right: Same distribution after the additional W-boson mass constraint
• Figure2_left: The di-jet combination with highest \PT for the electron analysis
• Figure2_right: The three di-jet combinations invariant masses among the top-quark candidates for the muon analysis
• Figure3_left: Expected distribution of the three-jet invariant mass after the standard selection for the muon analysis
• Figure3_right: The same after the W-boson mass constraint
• Figure4_left: Reconstructed top mass after W-boson mass constraint for the electron analysis.
• Figure4_right: The same distribution, but in addition requiring that the three highest PT jets are at eta < 1
• Figure5_left: Fit to the top signal.
• Figure5_right: Distribution of the expected statistical significance of the top signal in the peak as a function of the integrated luminosity for two background scenarios
• Figure6_left: Expected distribution of the three-jet invariant masses among the top-quark candidates after the requirement on the mass of the di-jet system in the electron channel
• Figure6_right: Same distribution for the muon channel
• Figure7: Number of jets tagged as coming from a b-quark in ttbar, single top and W-boson+jet events after the default electron selection
• Figure8_left: Reconstructed three-jet mass for ttbar , single top and $W$-boson + jet events for theelectron selection, requiring one or two jets tagged as coming from a b-quark.
• Figure8_right: Same distribution for the default selection + the W-boson mass constraint
• Figure8_left_color: Same as Figure_8_left
• Figure8_right_color: Same as Figure_8_right

Differential Distributions

• Figure9_left: Momentum distribution of the reconstructed three-jet mass
• Figure9_right: Rapidity distribution of the hadronically decaying top quark
• Figure10_left: Normalised di-top mass distribution for the more complex (dashed line) and the simple reconstruction (dotted line)
• Figure10_right: Expected reconstructed di-top mass distribution after all cuts
• Figure11_left: Distribution of PT and Y of hadronically decaying top quarks from truth information
• Figure11_right: Reconstructed distribution of PT and Y of hadronically decaying top quarks from fully simulated samples

Dilepton analyses:

• Figure12_left: Sigma(Delta R < 0.2) E_T variable for reconstructed electrons of the semi-leptonic ttbar background: in black are electrons matched to truth electrons, in white otherwise.
• Figure12_right: Delta(R) from a muon to the closest jet in the semi-leptonic ttbar sample. In white are muons matched to truth muons, in black are muons that are close to a b-quark
• Figure12_left_color: Same as Figure_12_left
• Figure12_right_color: Same as Figure_12_right
• Figure13_left: Di-lepton mass in signal, semi-leptonic ttbar and Z events
• Figure13_right: Distribution of missing ET for signal and various backgrounds
• Figure13_left_color: Same as Figure_13_left
• Figure13_right_color: Same as Figure_13_right
• Figure14_left: Monte Carlo e-mu template spanning the plane missing ET and number of jets for ttbar
• Figure14_center: Monte Carlo e-mu template spanning the plane missing ET and number of jets for ww
• Figure14_right: Monte Carlo e-mu template spanning the plane missing ET and number of jets for Z in tautau
• Figure15_left: Total composition of the inclusive di-lepton selection versus number of jets
• Figure15_right: Projected significance from pseudo-experiments for the inclusive template fit versus integrated luminosity including all channels and all systematic uncertainties
• Figure16: Distribution of Delta(phi) between the highest PT lepton and the missing momentum vector for (a) signal, (b) background and (c) signal/background composition according to the ratio obtained from the cut analysis

Single Top (T8)

t-channel cross-section measurement:

Event selection :

• Figure 1-left Probability density function for signal and background of the btagged jet pT after the t-channel selection;
• Figure 1-right Signal and background distri butions of jet multiplicity with pT above 30 geV/c after the t-channel selection for an integrated luminosity of 1 fb-1;

Systematic uncertainty :

• Figure 2-left Variation of the t-channel jet multiplicity for loose jets (pT>15 GeV) due to ISR/FSR parameter variation;
• Figure 2-right Variation of the t-channel jet multiplicity for tight jets (pT> 30 GeV) due to ISR/FSR parameter variation;

Event yields for an integrated luminosity of 1 fb-1:

• Figure 3-left Boosted Decision Tree output for signal and background after the btagged jet pT cut
• Figure 3-right Leptonic top quark mass distribution after a cut on the BDT output at 0.6

s-channel cross-section measurement:

Distributions of the likelihood functions defined against five different background types for an integrated luminosity of 1 fb-1:

• Figure 4a Likelihood function against top pair in the lepton+jet channel
• Figure 4b Likelihood function against top pair in the dilepton channel
• Figure 4c Likelihood function against top pair in the tau channel
• Figure 4d Likelihood function against W+jets background
• Figure 4e Likelihood function against t-channel background

W+t channel cross-section measurement:

Distributions of BDT output defined in the 3-jet final state channel for an integrated luminosity of 1 fb-1:

• Figure 5a BDT against top pair in the lepton+jet channel
• Figure 5b BDT against the W+jet background
• Figure 5c BDT against top pair in the dilepton channel
• Figure 5d BDT against the t-channel background

Top Mass (T9)

• Figure 1: b-tagging efficiency as a function of light jet rejection in ttbar events
• Figure 2, left: Light jet multiplicity in lepton+jets events before (solid line) and after (dashed line) requiring that the jet pT be greater than 40 GeV
• Figure 2 right: b jet multiplicity in lepton+jets events before (solid line) and after (dashed line) requiring that the jet pT be greater than 40 GeV
• Figure 3: Invariant mass of light jet pairs for events with only two light jets
• Figure 4: Hadronic W boson mass after chi2 minimization
• Figure 5: Energy correction factors estimated by the chi2 minimization
• Figure 6: Hadronic W boson mass (geometric method)
• Figure 7: Ratio of Etmiss to the generated neutrino transverse momentum
• Figure 8, left: Transverse W boson mass, before modification
• Figure 8, right: Transverse W boson mass, after modification
• Figure 9: Invariant mass of the hadronic W boson and the leptonic b-jet for events satisfying C1 cut
• Figure 10: Invariant mass of the lepton and the leptonic b-jet for events satisfying C1 and C2 cuts
• Figure 11: Distribution of X1 = E*(W) - E*(b had) for events passing C2 and C3 cuts
• Figure 12: Distribution of X2 = 2E*(b had) for events passing C2, C3 and C4 cuts
• Figure 13, left: Hadronic top quark mass reconstructed with the chi2 minimization method, after C0 cut
• Figure 13, right: Hadronic top quark mass reconstructed with the chi2 minimization method, after C2 and C3 cuts
• Figure 14, left: Hadronic top quark mass reconstructed with the geometric method, after C1, C2 and C3 cuts
• Figure 14, right: Hadronic top quark mass reconstructed with the geometric method, after C2, C3, C4 and C5 cuts
• Figure 15, left: Hadronic top quark mass reconstructed with the geometric method, with rescaling, after C1, C2 and C3 cuts
• Figure 15, right: Hadronic top quark mass reconstructed with the geometric method, with rescaling, after C2, C3, C4 and C5 cuts
• Figure 16: chi2 distribution (with combinatorial background) with cuts C2 and C3 applied
• Figure 17: Top quark mass as a function of chi2.
• Figure 18, left: Pull distribution for the top quark mass measurement, with chi2 minimization method
• Figure 18, right: Pull distribution for the top quark mass measurement, with geometric method
• Figure 19, left: Light jet multiplicity for several values of ISR/FSR parameters
• Figure 19, right: b-jet multiplicity for several values of ISR/FSR parameters
• Figure 20: Reconstructed top mass as a function of the generated top mass, with chi2 minimization method
• Figure 21: Difference between the reconstructed and generated top mass, as a function of the latter
• Figure 22, left: Events with only 1 b-tagged jet, with rescaling and after purification cuts (C1, C3 and C6)
• Figure 22, right: Events with only 1 b-tagged jet, with rescaling and after purification cuts (C3, C4, C5 and C6)
• Figure 23, left: Events without b-tagging with the geometric method and after purification cuts (C1 and C3)
• Figure 23, right: Events without b-tagging with the geometric method and after purification cuts (C3, C4 and C5)
• Figure 24, left: Events without b-tagging: comparison between background and event mixing samples for two jets invariant mass
• Figure 24, right: Events without b-tagging: comparison between background and event mixing samples for three jets invariant mass

Top Properties (T7)

• Figure 1: Invariant mass of leptons and b-jets from the same top quark (full line) and from different top quarks (dashed line)
• Figure 2: b-jet charge associated to positive (full line) and negative (dashed line) leptons at generator level (a) and after the ℓb mass cut (b)
• Figure 3: The b-jet Qcomb distribution from S+B (full line) and B only (dashed line) (a); the top quark charge Qcomb (full line) and its background (dashed line) (b).
• Figure 4a: Number of b-jets (containing a non-isolated lepton) associated with positive high pT leptons vs the charge of the non-isolated lepton
• Figure 4b: Number of b-jets (containing a non-isolated lepton) associated with negative high pT leptons vs the charge of the non-isolated lepton
• Figure 5: Correction function (a) and reconstructed angular distribution in the W centre-of-mass system (b)
• Figure 6a: Reconstructed distribution for the spin correlation parameter A
• Figure 6b: Reconstructed distribution for the spin correlation parameter Ad
• Figure 7a: Discriminant variables (normalised to L = 1 fb−1) for the analysis without b-tagging
• Figure 7b: Discriminant variables (normalised to L = 1 fb−1) for the analysis using b-tag weights
• Figure 8a: Expected 68% CL allowed regions on the Wtb anomalous couplings gR vs gL
• Figure 8b: Expected 68% CL allowed regions on the Wtb anomalous couplings gR vs VR
• Figure 9a: Normalised discriminant variables for the t→qγ channel (isolated lepton=electron)
• Figure 9b: Normalised discriminant variables for the t→qγ channel (isolated lepton=muon)
• Figure 9c: Normalised discriminant variables for the t→qγ channel (isolated lepton=electron+muon)
• Figure 9d: Normalised discriminant variables for the t→qZ channel (isolated lepton=electron)
• Figure 9e: Normalised discriminant variables for the t→qZ channel (isolated lepton=muon)
• Figure 9f: Normalised discriminant variables for the t→qZ channel (isolated lepton=electron+muon)
• Figure 9g: Normalised discriminant variables for the t→qgluon channel (isolated lepton=electron)
• Figure 9h: Normalised discriminant variables for the t→qgluon channel (isolated lepton=muon)
• Figure 9i: Normalised discriminant variables for the t→qgluon channel (isolated lepton=electron+muon)
• Figure 10: Observed and expected 95%CL limits on BR(t→qγ) vs BR(t→qZ)
• Figure 11: Standard Model ttbar mass spectrum
• Figure 12: A 700 GeV Z′ reconstructed mass distribution
• Figure 13: Reconstruction efficiency of Standard Model ttbar pairs as a function of the ttbar mass
• Figure 14: Reconstruction efficiency of Z′→ttbar resonances as a function of the Z′ mass
• Figure 15: Z′ mass resolution
• Figure 16: 5σ discovery potential of a generic ttbar resonance as a function of luminosity
• Figure 17: Expected ttbar invariant mass spectrum

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-- MartineBosman - 20 Nov 2008

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