1// -*- C++ -*-
  2#include "Rivet/Analysis.hh"
  3#include "Rivet/Projections/FinalState.hh"
  4#include "Rivet/Projections/FastJets.hh"
  5
  6namespace Rivet {
  7
  8
  9  /// Measurement of multi-jet cross sections
 10  class ATLAS_2011_S9128077 : public Analysis {
 11  public:
 12
 13    /// Constructor
 14    RIVET_DEFAULT_ANALYSIS_CTOR(ATLAS_2011_S9128077);
 15
 16
 17    /// @name Analysis methods
 18    //@{
 19
 20    /// Book histograms and initialise projections before the run
 21    void init() {
 22
 23      // Projections
 24      const FinalState fs;
 25      FastJets j4(fs, FastJets::ANTIKT, 0.4);
 26      j4.useInvisibles();
 27      declare(j4, "AntiKtJets04");
 28      FastJets j6(fs, FastJets::ANTIKT, 0.6);
 29      j6.useInvisibles();
 30      declare(j6, "AntiKtJets06");
 31
 32      // Persistent histograms
 33      book(_h_jet_multi_inclusive ,1, 1, 1);
 34      book(_h_jet_multi_ratio, 2, 1, 1, true);
 35      _h_jet_pT.resize(4);
 36      book(_h_jet_pT[0] ,3, 1, 1);
 37      book(_h_jet_pT[1] ,4, 1, 1);
 38      book(_h_jet_pT[2] ,5, 1, 1);
 39      book(_h_jet_pT[3] ,6, 1, 1);
 40      book(_h_HT_2 ,7, 1, 1);
 41      book(_h_HT_3 ,8, 1, 1);
 42      book(_h_HT_4 ,9, 1, 1);
 43      //
 44      book(_h_pTlead_R06_60_ratio, 10, 1, 1);
 45      book(_h_pTlead_R06_80_ratio, 11, 1, 1);
 46      book(_h_pTlead_R06_110_ratio, 12, 1, 1);
 47      book(_h_pTlead_R04_60_ratio, 13, 1, 1);
 48      book(_h_pTlead_R04_80_ratio, 14, 1, 1);
 49      book(_h_pTlead_R04_110_ratio, 15, 1, 1);
 50      book(_h_HT2_R06_ratio, 16, 1, 1);
 51      book(_h_HT2_R04_ratio, 17, 1, 1);
 52
 53      // Temporary histograms to be divided for the dsigma3/dsigma2 ratios
 54      book(_h_tmp_pTlead_R06_60_2 , "_pTlead_R06_60_2",  refData(10, 1, 1));
 55      book(_h_tmp_pTlead_R06_80_2 , "_pTlead_R06_80_2",  refData(11, 1, 1));
 56      book(_h_tmp_pTlead_R06_110_2, "_pTlead_R06_110_2", refData(12, 1, 1));
 57      book(_h_tmp_pTlead_R06_60_3 , "_pTlead_R06_60_3",  refData(10, 1, 1));
 58      book(_h_tmp_pTlead_R06_80_3 , "_pTlead_R06_80_3",  refData(11, 1, 1));
 59      book(_h_tmp_pTlead_R06_110_3, "_pTlead_R06_110_3", refData(12, 1, 1));
 60      //
 61      book(_h_tmp_pTlead_R04_60_2 , "_pTlead_R04_60_2",  refData(13, 1, 1));
 62      book(_h_tmp_pTlead_R04_80_2 , "_pTlead_R04_80_2",  refData(14, 1, 1));
 63      book(_h_tmp_pTlead_R04_110_2, "_pTlead_R04_110_2", refData(15, 1, 1));
 64      book(_h_tmp_pTlead_R04_60_3 , "_pTlead_R04_60_3",  refData(13, 1, 1));
 65      book(_h_tmp_pTlead_R04_80_3 , "_pTlead_R04_80_3",  refData(14, 1, 1));
 66      book(_h_tmp_pTlead_R04_110_3, "_pTlead_R04_110_3", refData(15, 1, 1));
 67      //
 68      book(_h_tmp_HT2_R06_2, "_HT2_R06_2", refData(16, 1, 1));
 69      book(_h_tmp_HT2_R06_3, "_HT2_R06_3", refData(16, 1, 1));
 70      book(_h_tmp_HT2_R04_2, "_HT2_R04_2", refData(17, 1, 1));
 71      book(_h_tmp_HT2_R04_3, "_HT2_R04_3", refData(17, 1, 1));
 72    }
 73
 74
 75    /// Perform the per-event analysis
 76    void analyze(const Event& event) {
 77      vector<FourMomentum> jets04;
 78      for (const Jet& jet : apply<FastJets>(event, "AntiKtJets04").jetsByPt(60.0*GeV)) {
 79        if (jet.abseta() < 2.8) {
 80          jets04.push_back(jet.momentum());
 81        }
 82      }
 83
 84      if (jets04.size() > 1 && jets04[0].pT() > 80.0*GeV) {
 85        for (size_t i = 2; i <= jets04.size(); ++i) {
 86          _h_jet_multi_inclusive->fill(i);
 87        }
 88
 89        double HT = 0.0;
 90        for (size_t i = 0; i < jets04.size(); ++i) {
 91          if (i < _h_jet_pT.size()) _h_jet_pT[i]->fill(jets04[i].pT());
 92          HT += jets04[i].pT();
 93        }
 94
 95        if (jets04.size() >= 2) _h_HT_2->fill(HT);
 96        if (jets04.size() >= 3) _h_HT_3->fill(HT);
 97        if (jets04.size() >= 4) _h_HT_4->fill(HT);
 98
 99        double pT1(jets04[0].pT()), pT2(jets04[1].pT());
100        double HT2 = pT1 + pT2;
101        if (jets04.size() >= 2) {
102          _h_tmp_HT2_R04_2->fill(HT2);
103          _h_tmp_pTlead_R04_60_2->fill(pT1);
104          if (pT2 > 80.0*GeV) _h_tmp_pTlead_R04_80_2->fill(pT1);
105          if (pT2 > 110.0*GeV) _h_tmp_pTlead_R04_110_2->fill(pT1);
106        }
107        if (jets04.size() >= 3) {
108          double pT3(jets04[2].pT());
109          _h_tmp_HT2_R04_3->fill(HT2);
110          _h_tmp_pTlead_R04_60_3->fill(pT1);
111          if (pT3 > 80.0*GeV) _h_tmp_pTlead_R04_80_3->fill(pT1);
112          if (pT3 > 110.0*GeV) _h_tmp_pTlead_R04_110_3->fill(pT1);
113        }
114      }
115
116      /// @todo It'd be better to avoid duplicating 95% of the code!
117      vector<FourMomentum> jets06;
118      for (const Jet& jet : apply<FastJets>(event, "AntiKtJets06").jetsByPt(60.0*GeV)) {
119        if (jet.abseta() < 2.8) {
120          jets06.push_back(jet.momentum());
121        }
122      }
123      if (jets06.size() > 1 && jets06[0].pT() > 80.0*GeV) {
124        double pT1(jets06[0].pT()), pT2(jets06[1].pT());
125        double HT2 = pT1 + pT2;
126        if (jets06.size() >= 2) {
127          _h_tmp_HT2_R06_2->fill(HT2);
128          _h_tmp_pTlead_R06_60_2->fill(pT1);
129          if (pT2 > 80.0*GeV) _h_tmp_pTlead_R06_80_2->fill(pT1);
130          if (pT2 > 110.0*GeV) _h_tmp_pTlead_R06_110_2->fill(pT1);
131        }
132        if (jets06.size() >= 3) {
133          double pT3(jets06[2].pT());
134          _h_tmp_HT2_R06_3->fill(HT2);
135          _h_tmp_pTlead_R06_60_3->fill(pT1);
136          if (pT3 > 80.0*GeV) _h_tmp_pTlead_R06_80_3->fill(pT1);
137          if (pT3 > 110.0*GeV) _h_tmp_pTlead_R06_110_3->fill(pT1);
138        }
139      }
140
141    }
142
143
144    /// Normalise histograms etc., after the run
145    void finalize() {
146
147      // Normalize std histos
148      scale(_h_jet_multi_inclusive, crossSectionPerEvent());
149      scale(_h_jet_pT[0], crossSectionPerEvent());
150      scale(_h_jet_pT[1], crossSectionPerEvent());
151      scale(_h_jet_pT[2], crossSectionPerEvent());
152      scale(_h_jet_pT[3], crossSectionPerEvent());
153      scale(_h_HT_2, crossSectionPerEvent());
154      scale(_h_HT_3, crossSectionPerEvent());
155      scale(_h_HT_4, crossSectionPerEvent());
156
157      scale(_h_tmp_pTlead_R06_60_2 , crossSectionPerEvent());
158      scale(_h_tmp_pTlead_R06_80_2 , crossSectionPerEvent());
159      scale(_h_tmp_pTlead_R06_110_2, crossSectionPerEvent());
160      scale(_h_tmp_pTlead_R06_60_3 , crossSectionPerEvent());
161      scale(_h_tmp_pTlead_R06_80_3 , crossSectionPerEvent());
162      scale(_h_tmp_pTlead_R06_110_3, crossSectionPerEvent());
163
164      scale(_h_tmp_pTlead_R04_60_2 , crossSectionPerEvent());
165      scale(_h_tmp_pTlead_R04_80_2 , crossSectionPerEvent());
166      scale(_h_tmp_pTlead_R04_110_2, crossSectionPerEvent());
167      scale(_h_tmp_pTlead_R04_60_3 , crossSectionPerEvent());
168      scale(_h_tmp_pTlead_R04_80_3 , crossSectionPerEvent());
169      scale(_h_tmp_pTlead_R04_110_3, crossSectionPerEvent());
170
171      scale(_h_tmp_HT2_R06_2, crossSectionPerEvent());
172      scale(_h_tmp_HT2_R06_3, crossSectionPerEvent());
173      scale(_h_tmp_HT2_R04_2, crossSectionPerEvent());
174      scale(_h_tmp_HT2_R04_3, crossSectionPerEvent());
175
176      // Fill inclusive jet multiplicity ratio
177      for (size_t b = 0; b < _h_jet_multi_ratio->numPoints(); ++b) {
178        if (_h_jet_multi_inclusive->bin(b).sumW() != 0) {
179          const double val = _h_jet_multi_inclusive->bin(b+1).sumW() / _h_jet_multi_inclusive->bin(b).sumW();
180          // @todo Shouldn't these be added in quadrature??
181          const double err = ( _h_jet_multi_inclusive->bin(b+1).relErr() + _h_jet_multi_inclusive->bin(b).relErr() ) * val;
182          _h_jet_multi_ratio->point(b).setY(val, err);
183        }
184        else {
185          _h_jet_multi_ratio->point(b).setY(0., 0.);
186        }
187      }
188
189      /// Create ratio histograms
190      divide(_h_tmp_pTlead_R06_60_3,_h_tmp_pTlead_R06_60_2, _h_pTlead_R06_60_ratio);
191      divide(_h_tmp_pTlead_R06_80_3,_h_tmp_pTlead_R06_80_2, _h_pTlead_R06_80_ratio);
192      divide(_h_tmp_pTlead_R06_110_3,_h_tmp_pTlead_R06_110_2, _h_pTlead_R06_110_ratio);
193      divide(_h_tmp_pTlead_R04_60_3,_h_tmp_pTlead_R04_60_2, _h_pTlead_R04_60_ratio);
194      divide(_h_tmp_pTlead_R04_80_3,_h_tmp_pTlead_R04_80_2, _h_pTlead_R04_80_ratio);
195      divide(_h_tmp_pTlead_R04_110_3,_h_tmp_pTlead_R04_110_2, _h_pTlead_R04_110_ratio);
196      divide(_h_tmp_HT2_R06_3,_h_tmp_HT2_R06_2, _h_HT2_R06_ratio);
197      divide(_h_tmp_HT2_R04_3,_h_tmp_HT2_R04_2, _h_HT2_R04_ratio);
198    }
199
200    //@}
201
202
203  private:
204
205    /// @name Histograms
206    //@{
207    Histo1DPtr _h_jet_multi_inclusive;
208    Scatter2DPtr _h_jet_multi_ratio;
209    vector<Histo1DPtr> _h_jet_pT;
210    Histo1DPtr _h_HT_2;
211    Histo1DPtr _h_HT_3;
212    Histo1DPtr _h_HT_4;
213    //@}
214
215    /// @name Ratio histograms
216    //@{
217    Scatter2DPtr _h_pTlead_R06_60_ratio, _h_pTlead_R06_80_ratio, _h_pTlead_R06_110_ratio;
218    Scatter2DPtr _h_pTlead_R04_60_ratio, _h_pTlead_R04_80_ratio, _h_pTlead_R04_110_ratio;
219    Scatter2DPtr _h_HT2_R06_ratio, _h_HT2_R04_ratio;
220    //@}
221
222    /// @name Temporary histograms to be divided for the dsigma3/dsigma2 ratios
223    //@{
224    Histo1DPtr _h_tmp_pTlead_R06_60_2, _h_tmp_pTlead_R06_80_2, _h_tmp_pTlead_R06_110_2;
225    Histo1DPtr _h_tmp_pTlead_R06_60_3, _h_tmp_pTlead_R06_80_3, _h_tmp_pTlead_R06_110_3;
226    Histo1DPtr _h_tmp_pTlead_R04_60_2, _h_tmp_pTlead_R04_80_2, _h_tmp_pTlead_R04_110_2;
227    Histo1DPtr _h_tmp_pTlead_R04_60_3, _h_tmp_pTlead_R04_80_3, _h_tmp_pTlead_R04_110_3;
228    Histo1DPtr _h_tmp_HT2_R06_2, _h_tmp_HT2_R06_3, _h_tmp_HT2_R04_2, _h_tmp_HT2_R04_3;
229    //@}
230
231  };
232
233
234
235  RIVET_DECLARE_ALIASED_PLUGIN(ATLAS_2011_S9128077, ATLAS_2011_I917599);
236
237
238}