1// -*- C++ -*-
  2#include "Rivet/Analysis.hh"
  3#include "Rivet/Projections/ChargedFinalState.hh"
  4#include "Rivet/Analyses/AliceCommon.hh"
  5
  6namespace Rivet {
  7
  8
  9  /// @brief ALICE PbPb at 2.76 TeV eta distributions, peripheral events.
 10  class ALICE_2016_I1394676 : public Analysis {
 11  public:
 12
 13    /// Constructor
 14    RIVET_DEFAULT_ANALYSIS_CTOR(ALICE_2016_I1394676);
 15
 16
 17    /// @name Analysis methods
 18    /// @{
 19
 20    /// Book histograms and initialise projections before the run
 21    void init() {
 22      // Initialise and register projections
 23      // Centrality projection.
 24      declareCentrality(ALICE::V0MMultiplicity(), "ALICE_2015_CENT_PBPB",
 25        "V0M","V0M");
 26      // Projections for the 2-out-of-3 trigger.
 27      declare(ChargedFinalState( (Cuts::eta > 2.8 && Cuts::eta < 5.1) &&
 28         Cuts::pT > 0.1*GeV), "VZERO1");
 29      declare(ChargedFinalState( (Cuts::eta > -3.7 && Cuts::eta < -1.7) &&
 30	 Cuts::pT > 0.1*GeV), "VZERO2");
 31      declare(ChargedFinalState(Cuts::abseta < 1. && Cuts::pT > 0.15*GeV), "SPD");
 32
 33      // Primary particles.
 34      declare(ALICE::PrimaryParticles(Cuts::abseta < 5.6),"APRIM");
 35
 36      // The centrality bins and the corresponding histograms and sow counters.
 37      centralityBins = { 40, 50, 60, 70, 80, 90 };
 38      for (int i = 0, N = centralityBins.size(); i < N; ++i) {
 39        book(histEta[centralityBins[i]], 1, 1, i + 1);
 40        book(sow[centralityBins[i]], "sow_" + toString(i));
 41      }
 42    }
 43
 44
 45    /// Perform the per-event analysis
 46    void analyze(const Event& event) {
 47      // Trigger projections.
 48      const ChargedFinalState& vz1 =
 49        apply<ChargedFinalState>(event,"VZERO1");
 50      const ChargedFinalState& vz2 =
 51        apply<ChargedFinalState>(event,"VZERO2");
 52      const ChargedFinalState& spd =
 53        apply<ChargedFinalState>(event,"SPD");
 54      int fwdTrig = (vz1.particles().size() > 0 ? 1 : 0);
 55      int bwdTrig = (vz2.particles().size() > 0 ? 1 : 0);
 56      int cTrig = (spd.particles().size() > 0 ? 1 : 0);
 57
 58      if (fwdTrig + bwdTrig + cTrig < 2) vetoEvent;
 59      const CentralityProjection& cent = apply<CentralityProjection>(event,"V0M");
 60      double c = cent();
 61      // No centralities below 30 %
 62      if (c < 30.) return;
 63      // Find the correct centrality histogram
 64      auto hItr = histEta.upper_bound(c);
 65      if (hItr == histEta.end()) return;
 66      // Find the correct sow.
 67      auto sItr = sow.upper_bound(c);
 68      if (sItr == sow.end()) return;
 69      sItr->second->fill();
 70
 71      // Fill the histograms.
 72      for ( const auto& p :
 73        apply<ALICE::PrimaryParticles>(event,"APRIM").particles() )
 74        if(p.abscharge() > 0) hItr->second->fill(p.eta());
 75
 76    }
 77
 78
 79    /// Normalise histograms etc., after the run
 80    void finalize() {
 81
 82      for (int i = 0, N = centralityBins.size(); i < N; ++i)
 83        histEta[centralityBins[i]]->scaleW(1./sow[centralityBins[i]]->sumW());
 84
 85    }
 86
 87    /// @}
 88
 89
 90    /// @name Histograms
 91    /// @{
 92     vector<double> centralityBins;
 93     map<double,Histo1DPtr> histEta;
 94     map<double, CounterPtr> sow;
 95    /// @}
 96
 97
 98  };
 99
100
101  RIVET_DECLARE_PLUGIN(ALICE_2016_I1394676);
102
103
104}