Rivet analyses

Mass distributions in B_c⁺ → J/ψ+ π⁺π⁺π⁻, K⁺K⁻π⁺ and K⁺π⁺π⁻

Experiment: LHCB (LHC)

Inspire ID: 1960979

Status: VALIDATED NOHEPDATA

Authors: - Peter Richardson

References: - JHEP 01 (2022) 065

Beams: * *

Beam energies: ANY

Run details: - Any process producing B_c+, originally pp

Mass distributions in B_c⁺ → J/ψ+ π⁺π⁺π⁻, K⁺K⁻π⁺ and K⁺π⁺π⁻. The data were read from the plots in the paper and may not be corrected for efficiency and acceptance.

Source code:`LHCB_2022_I1960979.cc`

// -*- C++ -*-
#include "Rivet/Analysis.hh"
#include "Rivet/Projections/UnstableParticles.hh"
#include "Rivet/Projections/DecayedParticles.hh"

namespace Rivet {


  /// @brief B_c - > jpsi + 3 charged hadrons
  class LHCB_2022_I1960979 : public Analysis {
  public:

    /// Constructor
    RIVET_DEFAULT_ANALYSIS_CTOR(LHCB_2022_I1960979);


    /// @name Analysis methods
    /// @{

    /// Book histograms and initialise projections before the run
    void init() {
      UnstableParticles ufs = UnstableParticles(Cuts::abspid==541);
      declare(ufs, "UFS");
      DecayedParticles BC(ufs);
      BC.addStable( PID::PI0);
      BC.addStable( PID::K0S);
      BC.addStable( PID::JPSI);
      declare(BC, "BC");
      for(unsigned int ix=0;ix<4;++ix) {
    for(unsigned int iy=0;iy<2;++iy) {
      if(iy==1&&ix>1) continue;
      book(_h[ix][iy],1+ix,1,1+iy);
    }
      }
    }


    /// Perform the per-event analysis
    void analyze(const Event& event) {
      static const map<PdgId,unsigned int> & mode1   = { { 443,1}, { 211,2}, {-211,1} };
      static const map<PdgId,unsigned int> & mode1CC = { { 443,1}, {-211,2}, { 211,1} };
      static const map<PdgId,unsigned int> & mode2   = { { 443,1}, { 321,1}, {-321,1}, { 211,1} };
      static const map<PdgId,unsigned int> & mode2CC = { { 443,1}, { 321,1}, {-321,1}, {-211,1} };
      static const map<PdgId,unsigned int> & mode3   = { { 443,1}, { 211,1}, {-211,1}, { 321,1} };
      static const map<PdgId,unsigned int> & mode3CC = { { 443,1}, { 211,1}, {-211,1}, {-321,1} };
      static const map<PdgId,unsigned int> & mode4   = { { 443,1}, { 321,2}, {-321,1} };
      static const map<PdgId,unsigned int> & mode4CC = { { 443,1}, { 321,1}, {-321,2} };
      DecayedParticles BC = apply<DecayedParticles>(event, "BC");
      // loop over particles
      for(unsigned int ix=0;ix<BC.decaying().size();++ix) {
    int sign = BC.decaying()[ix].pid()/BC.decaying()[ix].abspid();
    if ((sign== 1 && BC.modeMatches(ix,4,mode1  )) ||
        (sign==-1 && BC.modeMatches(ix,4,mode1CC))) {
      const Particle  & pim = BC.decayProducts()[ix].at(-sign*211)[0];
      const Particles & pip = BC.decayProducts()[ix].at( sign*211);
      _h[0][0]->fill((pim.momentum()+pip[0].momentum()+pip[1].momentum()).mass());
      _h[0][1]->fill((pim.momentum()+pip[0].momentum()).mass());
      _h[0][1]->fill((pim.momentum()+pip[1].momentum()).mass());
    }
    else if((sign== 1 && BC.modeMatches(ix,4,mode2  )) ||
        (sign==-1 && BC.modeMatches(ix,4,mode2CC))) {
      const Particle  & Kp  = BC.decayProducts()[ix].at( sign*321)[0];
      const Particle  & Km  = BC.decayProducts()[ix].at(-sign*321)[0];
      const Particle  & pip = BC.decayProducts()[ix].at( sign*211)[0];
      _h[1][0]->fill((Km.momentum()+pip.momentum()).mass());
      _h[1][1]->fill((Km.momentum()+Kp .momentum()).mass());
    }
    else if((sign== 1 && BC.modeMatches(ix,4,mode3  )) ||
        (sign==-1 && BC.modeMatches(ix,4,mode3CC))) {
      const Particle  & pim  = BC.decayProducts()[ix].at(-sign*211)[0];
      const Particle  & Kp   = BC.decayProducts()[ix].at( sign*321)[0];
      _h[2][0]->fill((Kp.momentum()+pim.momentum()).mass());
    }
    else if((sign== 1 && BC.modeMatches(ix,4,mode4  )) ||
        (sign==-1 && BC.modeMatches(ix,4,mode4CC))) {
      const Particle  & Km = BC.decayProducts()[ix].at(-sign*321)[0];
      const Particles & Kp = BC.decayProducts()[ix].at( sign*321);
      _h[3][0]->fill((Kp[0].momentum()+Km.momentum()).mass());
      _h[3][0]->fill((Kp[1].momentum()+Km.momentum()).mass());
    }
      }
    }


    /// Normalise histograms etc., after the run
    void finalize() {
      for(unsigned int ix=0;ix<3;++ix) {
    for(unsigned int iy=0;iy<2;++iy) {
      if(iy==1&&ix>1) continue;
      normalize(_h[ix][iy],1.,false);
    }
      }
    }

    /// @}


    /// @name Histograms
    /// @{
    Histo1DPtr _h[4][2];
    /// @}


  };


  RIVET_DECLARE_PLUGIN(LHCB_2022_I1960979);

}

Rivet analyses

Mass distributions in Bc+ → J/ψ+ π+π+π−, K+K−π+ and K+π+π−

Source code:LHCB_2022_I1960979.cc

Mass distributions in B_c⁺ → J/ψ+ π⁺π⁺π⁻, K⁺K⁻π⁺ and K⁺π⁺π⁻

Source code:`LHCB_2022_I1960979.cc`