Rivet analyses

title: MC_CORRELATORS_EXAMPLE

Example analysis for correlators framework

Experiment: None ()

Status: UNVALIDATED

Authors: none listed

References: none listed

Beams: * *

Beam energies: ANY

Run details: - any

Example analysis for how to implement a flow analysis using the correlators framework.

Source code:MC_CORRELATORS_EXAMPLE.cc

```c++ // -- C++ --

include "Rivet/Analysis.hh"

include "Rivet/Projections/ChargedFinalState.hh"

include "Rivet/Projections/PrimaryParticles.hh"

include "Rivet/Tools/Correlators.hh"

namespace Rivet {

class MC_CORRELATORS_EXAMPLE : public CumulantAnalysis { public:

/// @name Constructors etc.
/// @{

/// Constructor
MC_CORRELATORS_EXAMPLE()
    : CumulantAnalysis("MC_CORRELATORS_EXAMPLE") { }
/// @}


/// @name Analysis methods
/// @{
/// Book histograms and initialise projections before the run
void init() {

  ChargedFinalState cfs(Cuts::abseta < 1.0);
  declare(cfs, "CFS");
  ChargedFinalState pp(Cuts::abseta < 2.0);
  declare(pp, "PP");
  book(h_c22, "c22", 120, 0, 120);
  book(h_c23, "c23", 120, 0, 120);
  book(h_v22pT, "v22pT", 10, 0, 10);
  ec22 = bookECorrelator<2, 2>("ec22", *h_c22);
  ec23 = bookECorrelator<3, 2>("ec32", *h_c22);
  ec22pT = bookECorrelator<2, 2>("ec22pT", *h_v22pT);
  pair<int, int> max = getMaxValues();
  // Declare correlator projections.
  declare(Correlators(pp, max.first, max.second, *h_v22pT), "CRS");
}

/// Perform the per-event analysis
void analyze(const Event& event) {
  const Correlators& c = apply<Correlators>(event, "CRS");
  ec22->fill(apply<ChargedFinalState>(event, "CFS").particles().size(), c);
  ec23->fill(apply<ChargedFinalState>(event, "CFS").particles().size(), c);
  ec22pT->fill(c);
}

/// Normalise histograms etc., after the run
void finalize() {
  cnTwoInt(h_c22, ec22);
  cnTwoInt(h_c23, ec23);
  vnTwoDiff(h_v22pT, ec22pT);
}

/// @}

private:

/// @name Histograms
/// @{
Scatter2DPtr h_c22;
Scatter2DPtr h_v22pT;
ECorrPtr ec22;
ECorrPtr ec22pT;
Scatter2DPtr h_c23;
ECorrPtr ec23;
/// @}

};

RIVET_DECLARE_PLUGIN(MC_CORRELATORS_EXAMPLE);

} ```