Rivet analyses

CDF Run 2 min bias charged multiplicity analysis

Experiment: CDF (Tevatron Run 2)

Spires ID: None

Status: OBSOLETE

Authors: - Holger Schulz

References: - CDF public note 9936 - http://www-cdf.fnal.gov/physics/new/qcd/minbias_mult09/multpage.html

Beams: p- p+

Beam energies: (980.0, 980.0)GeV

Run details: - pp̄ QCD interactions at 1960~GeV. Particles with cτ > 10 mm should be set stable.

Niccolo Moggi’s min bias analysis. Minimum bias events are used to measure the charged multiplicity distribution. The multiplicity distribution was not published in S8233977 but the numbers and a public note are available from the CDF website given above. Note: the systematic and statistical errors in Rivet were added in quadrature.

Source code:CDF_2009_NOTE_9936.cc

// -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/ChargedFinalState.hh"
#include "Rivet/Projections/TriggerCDFRun2.hh"

namespace Rivet {


  class CDF_2009_NOTE_9936 : public Analysis {
  public:

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

    /// Constructor
    RIVET_DEFAULT_ANALYSIS_CTOR(CDF_2009_NOTE_9936);

    /// @}


  public:

    /// @name Analysis methods
    /// @{

    /// Book histograms and initialise projections before the run
    void init() {

      declare(TriggerCDFRun2(), "Trigger");

      declare(ChargedFinalState((Cuts::etaIn(-1.0, 1.0) && Cuts::pT >=  0.4*GeV)), "CFS");

      book(_hist_nch ,1, 1, 1);
    }


    /// Perform the per-event analysis
    void analyze(const Event& event) {
      // MinBias Trigger
      const bool trigger = apply<TriggerCDFRun2>(event, "Trigger").minBiasDecision();
      if (!trigger) vetoEvent;

      // Get events charged multiplicity and fill histogram
      const ChargedFinalState& cfs = apply<ChargedFinalState>(event, "CFS");
      _hist_nch->fill(cfs.size());

    }


    /// Normalise histograms etc., after the run
    void finalize() {
      normalize(_hist_nch);
    }

    /// @}

  private:

    Histo1DPtr _hist_nch;

  };



  RIVET_DECLARE_PLUGIN(CDF_2009_NOTE_9936);

}