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BELLE_2019_I1729723

$\bar{B}^0\to K^0_SK^\mp\pi^\pm$
Experiment: BELLE (KEKB)
Inspire ID: 1729723
Status: VALIDATED NOHEPDATA
Authors:
  • Peter Richardson
References:
  • Phys.Rev.D 100 (2019) 1, 011101
Beams: * *
Beam energies: ANY
Run details:
  • Any process producing B0 originally e+e- at Upsilon(4S)

Measurement of the mass distributions in the decays $\bar{B}^0\to K^0_SK^\mp\pi^\pm$. The data were read from the plots in the paper, but is corrected for detector efficiency.

Source code: BELLE_2019_I1729723.cc
 1// -*- C++ -*-
 2#include "Rivet/Analysis.hh"
 3#include "Rivet/Projections/UnstableParticles.hh"
 4#include "Rivet/Projections/DecayedParticles.hh"
 5
 6namespace Rivet {
 7
 8
 9  /// @brief B0 -> KS0 K-+ pi+-
10  class BELLE_2019_I1729723 : public Analysis {
11  public:
12
13    /// Constructor
14    RIVET_DEFAULT_ANALYSIS_CTOR(BELLE_2019_I1729723);
15
16
17    /// @name Analysis methods
18    /// @{
19
20    /// Book histograms and initialise projections before the run
21    void init() {
22      UnstableParticles ufs = UnstableParticles(Cuts::abspid==511);
23      declare(ufs, "UFS");
24      DecayedParticles B0(ufs);
25      B0.addStable(PID::PI0);
26      B0.addStable(PID::K0S);
27      B0.addStable(PID::ETA);
28      B0.addStable(PID::ETAPRIME);
29      declare(B0, "B0");
30      for(unsigned int ix=0;ix<3;++ix) {
31	for(unsigned int iy=0;iy<2;++iy) {
32	  book(_h[ix][iy],1+ix,1,1+iy);
33	}
34      }
35      book(_n,"TMP/nB0");
36    }
37
38
39    /// Perform the per-event analysis
40    void analyze(const Event& event) {
41      static const map<PdgId,unsigned int> & mode   = { { 310,1}, {-321,1}, { 211,1} };
42      static const map<PdgId,unsigned int> & modeCC = { { 310,1}, { 321,1}, {-211,1} };
43      DecayedParticles B0 = apply<DecayedParticles>(event, "B0");
44      // loop over particles
45      for(unsigned int ix=0;ix<B0.decaying().size();++ix) {
46	_n->fill();
47	unsigned int iloc(0);
48	int sign=1;
49      	if(B0.modeMatches(ix,3,mode)) {
50	  sign=1;
51	  iloc = B0.decaying()[ix].pid()>0 ? 1 : 0;
52	}
53	else if(B0.modeMatches(ix,3,modeCC)) {
54	  sign=-1;
55	  iloc = B0.decaying()[ix].pid()>0 ? 0 : 1;
56	}
57	else
58	  continue;
59     	const Particle & pip  = B0.decayProducts()[ix].at( sign*211)[0];
60     	const Particle & Km   = B0.decayProducts()[ix].at(-sign*321)[0];
61     	const Particle & K0   = B0.decayProducts()[ix].at(      310)[0];
62	_h[0][iloc]->fill((Km.momentum()+pip.momentum()).mass());
63	_h[1][iloc]->fill((K0.momentum()+pip.momentum()).mass());
64	_h[2][iloc]->fill((Km.momentum()+K0 .momentum()).mass());
65      }
66    }
67
68
69    /// Normalise histograms etc., after the run
70    void finalize() {
71      for(unsigned int ix=0;ix<3;++ix) {
72	for(unsigned int iy=0;iy<2;++iy) {
73	  scale(_h[ix][iy], 1e7/ *_n);
74	}
75      }
76    }
77
78    /// @}
79
80
81    /// @name Histograms
82    /// @{
83    Histo1DPtr _h[3][2];
84    CounterPtr _n;
85    /// @}
86
87
88  };
89
90
91  RIVET_DECLARE_PLUGIN(BELLE_2019_I1729723);
92
93}