Rivet analyses

Drell Yan production at low masses $4.8 < m_{⁺-} < 8.2 $ GeV at $\sqrt{s} = 200$ GeV

Experiment: PHENIX (RHIC)

Inspire ID: 1672015

Status: VALIDATED

Authors: - Hannes Jung

References: - Phys. Rev., D99(2019), 072003 - DOI:https://doi.org/10.1103/PhysRevD.99.072003 - arXiv: 1805.02448

Beams: p+ p+

Beam energies: (100.0, 100.0)GeV

Run details: none listed

PHENIX reports differential cross sections of μ⁺μ⁻ pairs from semileptonic heavy-flavor decays and the Drell-Yan production mechanism measured in p+p collisions at $\sqrt{s} = 200$ GeV at forward and backward rapidity (1.2 < |y| < 2.2). The μ⁺μ⁻ pairs from cc̄, bb̄, and Drell-Yan are separated using a template fit to unlike- and like-sign muon pair spectra in mass and p_T.

Source code:`PHENIX_2019_I1672015.cc`

// -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/FinalState.hh"
#include "Rivet/Projections/FastJets.hh"
#include "Rivet/Projections/IdentifiedFinalState.hh"
#include "Rivet/Projections/MissingMomentum.hh"
#include "Rivet/Projections/DileptonFinder.hh"

namespace Rivet {


  /// Drell Yan production at low masses at $\sqrt{s} = 200$ GeV
  class PHENIX_2019_I1672015 : public Analysis {
  public:

    /// Constructor
    RIVET_DEFAULT_ANALYSIS_CTOR(PHENIX_2019_I1672015);

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

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

      // Initialise and register projections
      DileptonFinder zfinder(91.2*GeV, 0.0, Cuts::abseta < 10. && Cuts::abspid == PID::MUON,
                             Cuts::massIn(4.0*GeV, 100.0*GeV), LeptonOrigin::PROMPT);
      declare(zfinder, "DileptonFinder");

      // Book histograms
      book(_h_pT ,1, 1, 1);
      book(_h_mass,2, 1, 1);
      int Nbin = 50;
      book(_h_m_DiMuon,"DiMuon_mass",Nbin,0.0,30.0);
      book(_h_pT_DiMuon,"DiMuon_pT",Nbin,0.0,20.0);
      book(_h_y_DiMuon,"DiMuon_y",Nbin,-8.0, 8.0);

    }


    /// Perform the per-event analysis
    void analyze(const Event& event) {

      const DileptonFinder& zfinder = apply<DileptonFinder>(event, "DileptonFinder");
      if (zfinder.bosons().size() < 1) vetoEvent;
      const FourMomentum& mom = zfinder.bosons()[0].mom();
      double mass = mom.mass()/GeV;
      double pt_DY   = mom.pT()/GeV;
      double y_DY    = abs(mom.rap());

      _h_m_DiMuon->fill(mass);
      _h_pT_DiMuon->fill(pt_DY);
      _h_y_DiMuon ->fill(y_DY);
      if (inRange( y_DY, 1.2, 2.2) && inRange(mass, 4.8, 8.2) && pt_DY > 0) {
        _h_pT->fill(pt_DY, 1./2./pt_DY/M_PI);
      }
      if (inRange( y_DY, 1.2, 2.2))  _h_mass->fill(mass);

    }


    /// Normalise histograms etc., after the run
    void finalize() {

      normalize(_h_m_DiMuon);
      normalize(_h_pT_DiMuon);
      normalize(_h_y_DiMuon);
      // Divide by 2 because of rapidity range
      scale(_h_pT, crossSection()/picobarn/sumOfWeights()/2.);
      scale(_h_mass, crossSection()/picobarn/sumOfWeights()/2.);

    }

    /// @}


    /// @name Histograms
    /// @{
    Histo1DPtr _h_pT, _h_mass;
    Histo1DPtr _h_m_DiMuon;
    Histo1DPtr _h_pT_DiMuon;
    Histo1DPtr _h_y_DiMuon;
    /// @}

  };


  RIVET_DECLARE_PLUGIN(PHENIX_2019_I1672015);

}

Rivet analyses

Drell Yan production at low masses $4.8 < m_{+-} < 8.2 $ GeV at $\sqrt{s} = 200$ GeV

Source code:PHENIX_2019_I1672015.cc

Drell Yan production at low masses $4.8 < m_{⁺-} < 8.2 $ GeV at $\sqrt{s} = 200$ GeV

Source code:`PHENIX_2019_I1672015.cc`