Rivet Analyses Reference

D0_2007_S7075677

$Z/\gamma^* + X$ cross-section shape, differential in $y(Z)$
Experiment: D0 (Tevatron Run 2)
Inspire ID: 744624
Status: VALIDATED
Authors:
  • Andy Buckley
  • Gavin Hesketh
  • Frank Siegert
References:Beams: p- p+
Beam energies: (980.0, 980.0) GeV
Run details:
  • Drell-Yan $p \bar{p} \to Z/\gamma^*$ + jets events at $\sqrt{s}$ = 1960 GeV. Needs mass cut on lepton pair to avoid photon singularity, looser than $71 < m_{ee} < 111$ GeV

Cross sections as a function of di-electron rapidity $p \bar{p}$ collisions at $\sqrt{s}$ = 1.96 TeV, based on an integrated luminosity of $0.4 \text{fb}^{-1}$.

Source code: D0_2007_S7075677.cc
 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
// -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/ZFinder.hh"

namespace Rivet {


  /// @brief Measurement of D0 Run II Z \f$ p_\perp \f$ diff cross-section shape
  ///
  /// @author Andy Buckley
  /// @author Gavin Hesketh
  /// @author Frank Siegert
  class D0_2007_S7075677 : public Analysis {
  public:

    RIVET_DEFAULT_ANALYSIS_CTOR(D0_2007_S7075677);


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

    /// Book histograms
    void init() {
      ZFinder zfinder(FinalState(), Cuts::open(), PID::ELECTRON,
                      71*GeV, 111*GeV, 0.2, ZFinder::ClusterPhotons::NODECAY, ZFinder::AddPhotons::YES);
      declare(zfinder, "ZFinder");

      book(_h_yZ ,1, 1, 1);
    }


    /// Do the analysis
    void analyze(const Event & e) {
      const ZFinder& zfinder = apply<ZFinder>(e, "ZFinder");
      if (zfinder.bosons().size() == 1) {
        const Particles& el(zfinder.constituents());
        if (el[0].pT() > 25*GeV || el[1].pT() > 25*GeV) {
          _h_yZ->fill(fabs(zfinder.bosons()[0].rapidity()));
        }
      } else {
        MSG_DEBUG("No unique lepton pair found.");
      }
    }


    // Finalize
    void finalize() {
      // Data seems to have been normalized for the avg of the two sides
      // (+ve & -ve rapidity) rather than the sum, hence the 0.5:
      normalize(_h_yZ, 0.5);
    }

    /// @}


  private:

    /// @name Histograms
    /// @{
    Histo1DPtr _h_yZ;
    /// @}

  };



  RIVET_DECLARE_ALIASED_PLUGIN(D0_2007_S7075677, D0_2007_I744624);

}