| 1 | | dede |
| | 1 | = The second !MadAnalysis 5 workshop on LHC recasting @ Korea = |
| | 2 | = Analysis 4: CMS-HIG-18-011 = |
| | 3 | |
| | 4 | ||= Students =|| || |
| | 5 | ||= Supervisor(s) =|| Robin Ducrocq || |
| | 6 | |
| | 7 | |
| | 8 | == 1. Analysis summary == |
| | 9 | |
| | 10 | |
| | 11 | == 2. Analysis global information == |
| | 12 | |
| | 13 | * CMS contact person: nobody |
| | 14 | * Center of mass energy: 13 TeV |
| | 15 | * Integrated luminosity: 35.9 fb−1 |
| | 16 | * Link to the public CMS page: http://cms-results.web.cern.ch/cms-results/public-results/publications/HIG-18-011/ |
| | 17 | |
| | 18 | == 3. Selection description == |
| | 19 | |
| | 20 | === 3.1 Trigger selection === |
| | 21 | |
| | 22 | Only events using single-electron OR single-muon triggers are accepted: |
| | 23 | - single-electron: one electron with pT > 24 GeV |
| | 24 | - single-muon: one muon with pT > 20 GeV |
| | 25 | |
| | 26 | PS: This part cannot usually be described by the fast-simulation of detector. |
| | 27 | |
| | 28 | === 3.2 Object definition === |
| | 29 | |
| | 30 | * electron: |
| | 31 | * pT > 7 GeV, |
| | 32 | * |eta|<2.47. Are excluded electrons in the end-cap, i.e. 1.37 < |eta| < 1.52. |
| | 33 | * 'medium' likelihood identification. |
| | 34 | * transverse impact parameter: |d0|/err(d0) < 5. |
| | 35 | * longitudinal impact parameter: |z_0 x sin\theta | < 0.5 mm |
| | 36 | * isolation criterion: |
| | 37 | * sum PT of tracks in a cone around the electron (the electron track is subtracted) of size = min(10 GeV/PT,0.2) < 6% electron PT. |
| | 38 | * sum ET of clusters in a cone around the electron (the electron cluster is subtracted) of size DR=0.2 < 6% electron PT. |
| | 39 | |
| | 40 | |
| | 41 | * muon: |
| | 42 | * pT > 7 GeV |
| | 43 | * |eta|<2.4 |
| | 44 | * 'medium' identification. |
| | 45 | * transverse impact parameter: |d0|/err(d0) < 3. |
| | 46 | * longitudinal impact parameter: |z_0 x sin\theta | < 0.5 mm |
| | 47 | * isolation criterion: sum PT of tracks in a cone around the muon (the muon track is subtracted) of size = min(10 GeV/PT,0.3) < 6% muon PT. |
| | 48 | |
| | 49 | * jet: |
| | 50 | * clustering: anti-kT with =0.4 |
| | 51 | * pT > 25 GeV |
| | 52 | * |eta|<2.5 |
| | 53 | * Pile-up rejection: jets with pT < 60 GeV and |η| < 2.4 are required to satisfy pile-up rejection criteria (JVT) |
| | 54 | |
| | 55 | * b-jet: MV2c20 algorithm. In simulation, the tagging algorithm gives a rejection factor of about 130 against light-quark and gluon jets, and about 4.5 against jets containing charm quarks. |
| | 56 | |
| | 57 | * preventing double-counting: |
| | 58 | * the closest jet within DR=0.2 cone of an electron is removed. |
| | 59 | * if, after the previous selection cut, the nearest jet of an electron is in DR=0.4 cone, then the electron is removed. |
| | 60 | * muons in a DR=0.4 cone around a given jet are removed. BUT if the jet has fewer than three associated tracks, the muon is kept. |
| | 61 | |
| | 62 | |
| | 63 | === 3.3 Cut-flow chart === |
| | 64 | |
| | 65 | '''Common:''' |
| | 66 | |
| | 67 | * 0. Trigger confirmation: at least one lepton (muon/electron) with PT > 25 GeV |
| | 68 | |
| | 69 | |
| | 70 | '''1. Analysis 1: SS-muons''' |
| | 71 | |
| | 72 | * 1.1. 2 muons of same charge, with PT > 25 GeV |
| | 73 | * 1.2. Events with additional leptons are vetoed |
| | 74 | * 1.3. MET > 40 GeV |
| | 75 | * 1.4. HT > 240 GeV |
| | 76 | * 1.5. At least 2 b-jets |
| | 77 | |
| | 78 | |
| | 79 | '''2. Analysis 2: trilepton analysis''' |
| | 80 | |
| | 81 | * 2.1. Exactly 3 leptons |
| | 82 | * 2.2. 2 opposite sign, same flavour leptons, and |
| | 83 | * 2.2. Leading lepton with PT > 25 GeV, the other leptons with PT > 20 GeV |
| | 84 | * 2.3. Defining 4 signal regions according the final states: |
| | 85 | * 3l-Z-1b4j |
| | 86 | * 3l-Z-2b3j |
| | 87 | * 3l-Z-2b4j |
| | 88 | * 3l-noZ-2b |
| | 89 | * 2.4. Compatibility with a Z: |
| | 90 | * [3l-Z-1b4j]+[3l-Z-2b3j]+[3l-Z-2b4j]: compatible with a Z i.e. (invM-MZ)<10 GeV |
| | 91 | * [3l-noZ-2b]: not compatible with a Z i.e. (invM-MZ)>10 GeV |
| | 92 | * 2.5. Number of light jets (no b-jet): |
| | 93 | * [3l-Z-2b3j]: #jets = 3 |
| | 94 | * [3l-Z-1b4j]+[3l-Z-3b4j]: #jets >= 4 |
| | 95 | * [3l-noZ-2b]: #jets = 2, 3 or 4 |
| | 96 | * 2.6. Number of b-jets: |
| | 97 | * [3l-Z-1b4j]: #b-jets = 1 |
| | 98 | * [3l-Z-2b3j]+[3l-Z-3b4j]+[3l-noZ-2b]: #b-jets >= 2 |
| | 99 | |
| | 100 | '''3. Analysis 3: tetralepton analysis''' |
| | 101 | |
| | 102 | * 3.1. Exactly 4 leptons |
| | 103 | * 3.2. 2 pairs of opposite sign |
| | 104 | * 3.3. At least one pair must have same flavour leptons |
| | 105 | * 3.4. We define Z1 = reconstructed Z from opposite-sign same-flavour pair the closest to the Z mass. We define Z2 = reconstructed Z from the other pair (same-flavour or not). |
| | 106 | * 3.5. Defining 4 signal regions according the final states: |
| | 107 | * 4l-DF-1b |
| | 108 | * 4l-DF-2b |
| | 109 | * 4l-SF-1b |
| | 110 | * 4l-SF-2b |
| | 111 | * 3.5. Cut on PT34 = scalar sum of the transverse momenta of the leptons used in Z2: |
| | 112 | * [4l-DF-1b]: PT34 > 35 GeV |
| | 113 | * [4l-SF-1b]: PT34 > 25 GeV |
| | 114 | * 3.6. MET: |
| | 115 | * [4l-SF-1b]: If |MZ2-MZ| > 10 GeV then imposing MET > 40 GeV else imposing MET > 80 GeV |
| | 116 | * [4l-SF-2b]: If |MZ2-MZ| < 10 GeV then imposing MET > 40 GeV |
| | 117 | * 3.7. Number of b-jets: |
| | 118 | * [4l-DF-1b]+[4l-SF-1b]: #b-jets = 1 |
| | 119 | * [4l-DF-2b]+[4l-SF-2b]: #b-jets >= 2 |
| | 120 | |
| | 121 | === 3.4 Definition of exotic observables === |
| | 122 | |
| | 123 | No exotic observables. |
| | 124 | |
| | 125 | == 3. Detector simulation == |
| | 126 | |
| | 127 | Official Delphes package could be enough. |
| | 128 | |
| | 129 | To improve the realism of the simulation, Delphes_Track could be used for cutting on D0. Is it necessary? To try... |
| | 130 | |
| | 131 | == 4. Validation material == |
| | 132 | |
| | 133 | === 4.1 Monte-Carlo samples === |
| | 134 | |
| | 135 | * LO (but xsections are normalized to NLO) |
| | 136 | * Model used: SM |
| | 137 | * Mtop = 172.5 GeV |
| | 138 | * Mhiggs = 125 GeV |
| | 139 | * processes = ttZ (including gamma*) & ttW (but no ttWW) |
| | 140 | * xsections: Table 5 of ATL-PHYS-PUB-2016-005 |
| | 141 | * MC generator program (name + version): MG5_aMC |
| | 142 | * Shower program (name + version): Pythia v8.210 |
| | 143 | * Tune of Pythia: A14 tune (see http://cds.cern.ch/record/1966419) |
| | 144 | * PDF set: NNPDF2.3LO |
| | 145 | * ME/PS merging???? |
| | 146 | |
| | 147 | === 4.2 Reference plots / cut-flows === |
| | 148 | |
| | 149 | * MC xsections and plots: http://cds.cern.ch/record/2120826/files/ATL-PHYS-PUB-2016-005.pdf?version=1: |
| | 150 | * Table 5 |
| | 151 | * Figure 5 |
| | 152 | |
| | 153 | * Final number of signal events after the selection in each signal region: |
| | 154 | * https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/TOPQ-2015-22/tabaux_06.pdf |
| | 155 | |
| | 156 | * Plots for Analysis 1: SS-muons: |
| | 157 | * Figure 1 of the paper |
| | 158 | |
| | 159 | * Plots for Analysis 2: trileptons |
| | 160 | * Figure 5 of the paper |
| | 161 | |
| | 162 | * Plots for Analysis 3: tetraleptons |
| | 163 | * Figure 6 of the paper |
| | 164 | |
| | 165 | * Rivet analyses |
| | 166 | |
| | 167 | |
| | 168 | == 4. Validation results == |
| | 169 | |
| | 170 | == 5. Reinterpretation (optional) == |
| | 171 | |
| | 172 | == 6. Questions / issues == |
| | 173 | |
| | 174 | |
