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BELLE_2009_I816632

$D_s^{(*)-}K^+$ mass distribution in $B^+\to D_s^{(*)-}K^+\pi^+$ decays
Experiment: BELLE (KEKB)
Inspire ID: 816632
Status: VALIDATED NOHEPDATA
Authors:
  • Peter Richardson
References:
  • Phys.Rev.D 80 (2009) 052005
Beams: * *
Beam energies: ANY
Run details:
  • Any process producing B+ mesons, originally Upsilon(4S) decays

Measurement of the $D_s^{(*)-}K^+$ mass distribution in $B^+\to D_s^{(*)-}K^+\pi^+$ decays. The data were read from the plots in the paper and may not be corrected for efficiency/acceptance, although the backgrounds given wre subtracted.

Source code: BELLE_2009_I816632.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 B+ -> D_s(*) K pi
10  class BELLE_2009_I816632 : public Analysis {
11  public:
12
13    /// Constructor
14    RIVET_DEFAULT_ANALYSIS_CTOR(BELLE_2009_I816632);
15
16
17    /// @name Analysis methods
18    /// @{
19
20    /// Book histograms and initialise projections before the run
21    void init() {
22      // Initialise and register projections
23      UnstableParticles ufs = UnstableParticles(Cuts::abspid==521);
24      declare(ufs, "UFS");
25      DecayedParticles BP(ufs);
26      BP.addStable( 431);
27      BP.addStable(-431);
28      BP.addStable( 433);
29      BP.addStable(-433);
30      declare(BP, "BP");
31      // histograms
32      for(unsigned int ix=0;ix<2;++ix) {
33	book(_h_mass[ix],1,1,1+ix);
34      }
35    }
36
37
38    /// Perform the per-event analysis
39    void analyze(const Event& event) {
40      static const map<PdgId,unsigned int> & mode1   = { { -431,1}, { 321,1}, { 211,1}};
41      static const map<PdgId,unsigned int> & mode1CC = { {  431,1}, {-321,1}, {-211,1}};
42      static const map<PdgId,unsigned int> & mode2   = { { -433,1}, { 321,1}, { 211,1}};
43      static const map<PdgId,unsigned int> & mode2CC = { {  433,1}, {-321,1}, {-211,1}};
44      DecayedParticles BP = apply<DecayedParticles>(event, "BP");
45      // loop over particles
46      for(unsigned int ix=0;ix<BP.decaying().size();++ix) {
47      	int sign=1, mode=0;
48      	if      (BP.modeMatches(ix,3,mode1  )) {
49	  mode = 0;
50	  sign = 1;
51	}
52      	else if (BP.modeMatches(ix,3,mode1CC)) {
53	  sign =-1;
54	  mode = 0;
55	}
56	else if      (BP.modeMatches(ix,3,mode2  )) {
57	  mode = 1;
58	  sign = 1;
59	}
60      	else if (BP.modeMatches(ix,3,mode2CC)) {
61	  sign =-1;
62	  mode = 1;
63	}
64      	else continue;
65	const Particle & Ds  = BP.decayProducts()[ix].at(-sign*(431+2*mode))[0];
66       	const Particle & Kp  = BP.decayProducts()[ix].at( sign*321)[0];
67       	_h_mass[mode]->fill((Ds.momentum()+Kp.momentum()).mass());
68      }
69    }
70
71
72    /// Normalise histograms etc., after the run
73    void finalize() {
74      for(unsigned int ix=0;ix<2;++ix) {
75	normalize(_h_mass[ix],1.,false);
76      }
77    }
78
79    /// @}
80
81
82    /// @name Histograms
83    /// @{
84    Histo1DPtr _h_mass[2];
85    /// @}
86
87
88  };
89
90
91  RIVET_DECLARE_PLUGIN(BELLE_2009_I816632);
92
93}