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BESIII_2022_I2051683

Mass distributions in the decay $D^+_s\to K^+K^-\pi^+\pi^+\pi^-$
Experiment: BESIII (BEPC)
Inspire ID: 2051683
Status: VALIDATED NOHEPDATA
Authors:
  • Peter Richardson
References: Beams: * *
Beam energies: ANY
Run details:
  • Any process producing D_s+ mesons

Measurement of the mass distributions in the decay $D^+_s\to K^+K^-\pi^+\pi^+\pi^-$ by BES. The data were read from the plots in the paper and therefore for some points the error bars are the size of the point. It is also not clear that any resolution effects have been unfolded.

Source code: BESIII_2022_I2051683.cc
  1// -*- C++ -*-
  2#include "Rivet/Analysis.hh"
  3#include "Rivet/Projections/UnstableParticles.hh"
  4
  5namespace Rivet {
  6
  7
  8  /// @brief Ds -> K+K-pi+pi+pi-
  9  class BESIII_2022_I2051683 : public Analysis {
 10  public:
 11
 12    /// Constructor
 13    RIVET_DEFAULT_ANALYSIS_CTOR(BESIII_2022_I2051683);
 14
 15
 16    /// @name Analysis methods
 17    /// @{
 18
 19    /// Book histograms and initialise projections before the run
 20    void init() {
 21      // Initialise and register projections
 22      declare(UnstableParticles(), "UFS");
 23      for(unsigned int ix=0;ix<10;++ix)
 24	book(_h[ix],1,1,1+ix);
 25    }
 26
 27    void findDecayProducts(const Particle & mother, unsigned int & nstable,
 28			   Particles & pip , Particles & pim ,
 29			   Particles & Kp  , Particles & Km  ) {
 30      for(const Particle & p : mother.children()) {
 31        int id = p.pid();
 32        if ( id == PID::KPLUS ) {
 33       	  Kp.push_back(p);
 34	  ++nstable;
 35	}
 36	else if (id == PID::KMINUS ) {
 37	  Km.push_back(p);
 38	  ++nstable;
 39	}
 40	else if (id == PID::PIPLUS) {
 41	  pip.push_back(p);
 42	  ++nstable;
 43	}
 44	else if (id == PID::PIMINUS) {
 45	  pim.push_back(p);
 46	  ++nstable;
 47	}
 48	else if (id == PID::PI0 || id == PID::K0S||id == PID::K0L) {
 49          ++nstable;
 50        }
 51	else if ( !p.children().empty() ) {
 52	  findDecayProducts(p, nstable, pip, pim, Kp , Km);
 53	}
 54	else
 55	  ++nstable;
 56      }
 57    }
 58
 59    /// Perform the per-event analysis
 60    void analyze(const Event& event) {
 61      for(const Particle& meson : apply<UnstableParticles>(event, "UFS").particles(Cuts::abspid== 431)) {
 62	unsigned int nstable(0);
 63	Particles pip, pim, Kp , Km;
 64	findDecayProducts(meson, nstable, pip, pim, Kp , Km);
 65	if (nstable!=5) continue;
 66	if(meson.pid()<0) {
 67	  swap(pim,pip);
 68	  swap(Kp,Km);
 69	}
 70	if(pip.size()==2&&Km.size()==1&&Kp.size()==1&&pim.size()==1) {
 71	  double mpippim[2] = {(pim[0].momentum()+pip[0].momentum()).mass(), 
 72			       (pim[0].momentum()+pip[1].momentum()).mass()};
 73	  if(mpippim[0]>mpippim[1]) {
 74	    swap(  pip[0],  pip[1]);
 75	    swap(mpippim[0],mpippim[1]);
 76	  }
 77	  double mKK = (Kp[0].momentum()+Km[0].momentum()).mass();
 78	  _h[0]->fill(mKK);
 79	  _h[1]->fill(mKK);
 80	  _h[2]->fill(mpippim[0]);
 81	  _h[3]->fill(mpippim[1]);
 82	  _h[4]->fill((Kp [0].momentum()+Km [0].momentum()+pim[0].momentum()).mass());
 83	  _h[5]->fill((Km [0].momentum()+pip[1].momentum()+pim[0].momentum()).mass());
 84	  _h[6]->fill((Kp [0].momentum()+pip[0].momentum()+pim[0].momentum()).mass());
 85	  _h[7]->fill((pim[0].momentum()+pip[0].momentum()+pip[1].momentum()).mass());
 86	  _h[8]->fill((Kp [0].momentum()+Km [0].momentum()+pip[1].momentum()+pim[0].momentum()).mass());
 87	  _h[9]->fill((Km [0].momentum()+pip[0].momentum()+pip[1].momentum()+pim[0].momentum()).mass());
 88	}
 89      }
 90    }
 91
 92
 93    /// Normalise histograms etc., after the run
 94    void finalize() {
 95      for(unsigned int ix=0;ix<10;++ix)
 96	normalize(_h[ix],1.,false);
 97    }
 98
 99    /// @}
100
101
102    /// @name Histograms
103    /// @{
104    Histo1DPtr _h[10];
105    /// @}
106
107
108  };
109
110
111  RIVET_DECLARE_PLUGIN(BESIII_2022_I2051683);
112
113}