Rivet analyses referenceDELPHI_2000_I524693Hadronization properties of $b$ quarks compared to light quarks in $e^+ e^-\to q \bar{q}$ from 183 GeV to 200 GeVExperiment: OPAL (LEP 2) Inspire ID: 524693 Status: VALIDATED Authors:
Beam energies: (91.5, 91.5); (94.5, 94.5); (96.0, 96.0); (98.0, 98.0); (100.0, 100.0); (103.0, 103.0) GeV Run details:
Measurements of the mean charged multiplicities separately for $b\bar b$, $c\bar{c}$ and light quark ($uds$) initiated events in $e^+e^-$ interactions at energies above the $Z^0$ mass. In addition to the energy points in the original paper one additional point at 206;GeV is included from a later preliminary result. Source code: DELPHI_2000_I524693.cc 1// -*- C++ -*-
2#include "Rivet/Analysis.hh"
3#include "Rivet/Projections/Beam.hh"
4#include "Rivet/Projections/FinalState.hh"
5#include "Rivet/Projections/ChargedFinalState.hh"
6#include "Rivet/Projections/Sphericity.hh"
7#include "Rivet/Projections/Thrust.hh"
8#include "Rivet/Projections/FastJets.hh"
9#include "Rivet/Projections/ParisiTensor.hh"
10#include "Rivet/Projections/Hemispheres.hh"
11#include <cmath>
12
13#define I_KNOW_THE_INITIAL_QUARKS_PROJECTION_IS_DODGY_BUT_NEED_TO_USE_IT
14#include "Rivet/Projections/InitialQuarks.hh"
15
16namespace Rivet {
17
18
19 /// @brief DELPHI multiplicities at various energies
20 ///
21 /// @author Peter Richardson
22 class DELPHI_2000_I524693 : public Analysis {
23 public:
24
25 RIVET_DEFAULT_ANALYSIS_CTOR(DELPHI_2000_I524693);
26
27
28 /// @name Analysis methods
29 /// @{
30
31 void init() {
32 // Projections
33 declare(Beam(), "Beams");
34 declare(ChargedFinalState(), "CFS");
35 declare(InitialQuarks(), "IQF");
36 book(_cLight, "/TMP/CLIGHT" );
37 book(_cCharm, "/TMP/CCHARM" );
38 book(_cBottom, "/TMP/CBOTTOM");
39
40 book(_wLight, "_weight_light");
41 book(_wCharm, "_weight_charm");
42 book(_wBottom,"_weight_bottom");
43
44 _mult.resize(4);
45 book(_mult[0], 1, 1, 1);
46 book(_mult[1], 1, 1, 2);
47 book(_mult[2], 1, 1, 3);
48 book(_mult[3], 1, 1, 4); // bottom minus light
49
50 }
51
52
53 void analyze(const Event& event) {
54 // Even if we only generate hadronic events, we still need a cut on numCharged >= 2.
55 const FinalState& cfs = apply<FinalState>(event, "CFS");
56 if (cfs.size() < 2) vetoEvent;
57
58
59 int flavour = 0;
60 const InitialQuarks& iqf = apply<InitialQuarks>(event, "IQF");
61
62 // If we only have two quarks (qqbar), just take the flavour.
63 // If we have more than two quarks, look for the highest energetic q-qbar pair.
64 if (iqf.particles().size() == 2) {
65 flavour = iqf.particles().front().abspid();
66 }
67 else {
68 map<int, double> quarkmap;
69 for (const Particle& p : iqf.particles()) {
70 if (quarkmap[p.pid()] < p.E()) {
71 quarkmap[p.pid()] = p.E();
72 }
73 }
74 double maxenergy = 0.;
75 for (int i = 1; i <= 5; ++i) {
76 if (quarkmap[i]+quarkmap[-i] > maxenergy) {
77 flavour = i;
78 }
79 }
80 }
81 const size_t numParticles = cfs.particles().size();
82 switch (flavour) {
83 case 1: case 2: case 3:
84 _wLight->fill();
85 _cLight->fill(numParticles);
86 break;
87 case 4:
88 _wCharm->fill();
89 _cCharm->fill(numParticles);
90 break;
91 case 5:
92 _wBottom->fill();
93 _cBottom->fill(numParticles);
94 break;
95 }
96 }
97
98
99 void finalize() {
100
101 // calculate the averages and diffs
102 if(_wLight->val() != 0.) scale(_cLight, 1./(*_wLight));
103 if(_wCharm->val() != 0.) scale(_cCharm, 1./(*_wCharm));
104 if(_wBottom->val() != 0.) scale(_cBottom, 1./(*_wBottom));
105 Counter _cDiff = *_cBottom - *_cLight;
106
107 // fill the histograms
108 for (unsigned int ix=1; ix < 5; ++ix) {
109 double val(0.), err(0.0);
110 if(ix==1) {
111 val = _cBottom->val();
112 err = _cBottom->err();
113 }
114 else if(ix==2) {
115 val = _cCharm->val();
116 err = _cCharm->err();
117 }
118 else if(ix==3) {
119 val = _cLight->val();
120 err = _cLight->err();
121 }
122 else if(ix==4) {
123 val = _cDiff.val();
124 err = _cDiff.err();
125 }
126 for (auto& b : _mult[ix-1]->bins()) {
127 if (inRange(sqrtS()/GeV, b.xMin(), b.xMax())) {
128 b.set(val, err);
129 }
130 }
131 }
132
133 }
134
135 /// @}
136
137
138 private:
139
140 vector<Estimate1DPtr> _mult;
141
142 /// @name Multiplicities
143 /// @{
144 CounterPtr _cLight;
145 CounterPtr _cCharm;
146 CounterPtr _cBottom;
147 /// @}
148
149 /// @name Weights
150 /// @{
151 CounterPtr _wLight;
152 CounterPtr _wCharm;
153 CounterPtr _wBottom;
154 /// @}
155
156 };
157
158
159
160 RIVET_DECLARE_ALIASED_PLUGIN(DELPHI_2000_I524693, DELPHI_2000_S4328825);
161
162}
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