| 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) |
| 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. |
| | 29 | === 3.3 Selection cuts === |
| 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 |
