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
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
| // -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/UnstableParticles.hh"
namespace Rivet {
/// @brief Delta++ rate and spectrum
class ARGUS_1989_I278932 : public Analysis {
public:
/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(ARGUS_1989_I278932);
/// @name Analysis methods
///@{
/// Book histograms and initialise projections before the run
void init() {
// Initialise and register projections
declare(UnstableParticles(), "UFS");
// histograms
book( _r_ups,1,1,2);
book(_r_cont,2,1,2);
book(_h_p,3,1,1);
book(_w_ups ,"TMP/w_ups" );
book(_w_cont,"TMP/w_cont");
}
/// Recursively walk the decay tree to find decay products of @a p
void findDecayProducts(Particle mother, Particles& delta) {
// dleta pdg code
static const long id = 2224;
for(const Particle & p: mother.children()) {
if(p.abspid() == id) {
delta.push_back(p);
}
else if(!p.children().empty())
findDecayProducts(p, delta);
}
}
/// Perform the per-event analysis
void analyze(const Event& event) {
UnstableParticles ufs = apply<UnstableParticles>(event, "UFS");
Particles ups = ufs.particles(Cuts::pid==553);
// continuum
if(ups.empty()) {
_w_cont->fill();
_r_cont->fill(sqrtS(),ufs.particles(Cuts::abspid==2224).size());
}
// upsilon decays
else {
for(const Particle & p : ups) {
_w_ups->fill();
Particles delta;
findDecayProducts(p,delta);
if(delta.empty()) continue;
LorentzTransform boost;
if (p.p3().mod() > 1*MeV)
boost = LorentzTransform::mkFrameTransformFromBeta(p.momentum().betaVec());
for(const Particle& del : delta) {
_r_ups->fill(9.46);
double mom = boost.transform(del.momentum()).p3().mod();
_h_p->fill(mom);
}
}
}
}
/// Normalise histograms etc., after the run
void finalize() {
if(_w_cont->effNumEntries()>0) {
scale(_r_cont, 1./ *_w_cont);
}
// direct upsilon decays, i.e. to gg gamma and ggg so need to renormalize
// factor and values from arxiv:0612019
if(_w_ups->effNumEntries()>0) {
double Bmumu=0.0249, rhad = 3.56;
double fact = 1.-(3.+rhad)*Bmumu;
scale(_r_ups, 1./fact / *_w_ups);
scale(_h_p , 100./fact / *_w_ups);
}
}
///@}
/// @name Histograms
///@{
Histo1DPtr _r_ups,_r_cont;
Histo1DPtr _h_p;
CounterPtr _w_ups,_w_cont;
///@}
};
RIVET_DECLARE_PLUGIN(ARGUS_1989_I278932);
}
|