Rivet analyses

title: LHCB_2014_I1308738

Fraction of $\Upsilon(1,2,3S)$ from $\chi_b(1,2,3P)$ decays at 7 and 8 TeV

Experiment: LHCB (LHC)

Inspire ID: 1308738

Status: VALIDATED

Authors: - Peter Richardson

References: - Eur.Phys.J.C 74 (2014) 3092, 2014

Beams: p+ p+

Beam energies: (3500.0, 3500.0); (4000.0, 4000.0)GeV

Run details: - chi_b(1,2,3P) and Upsilon(1,2,3S)

Measurement of the fraction of $\Upsilon(1,2,3S)$ from $\chi_b(1,2,3P)$ decays at 7 and 8 TeV.

Source code:LHCB_2014_I1308738.cc

```c++ // -- C++ --

include "Rivet/Analysis.hh"

include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {

/// @brief chi_b production at 7,8 TeV class LHCB_2014_I1308738 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(LHCB_2014_I1308738);


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

/// Book histograms and initialise projections before the run
void init() {

  declare(UnstableParticles(), "UFS");

  for (double eVal : allowedEnergies()) {
    const int en = int(eVal + 0.5);
    if (isCompatibleWithSqrtS(eVal)) _sqs = en;

    int ih = int(en == 8000) + 1;

    // decays to 1S
    for (size_t ix = 0; ix < 3; ++ix) {
      book(_h_pT_1S[en + ix], "TMP/Ups_1_" + toString(en + ix), refData(3 * ih - 2, 1, 1 + ix));
    }
    for (size_t ix = 0; ix < 2; ++ix) {
      book(_h_pT_1S[en + ix + 3], "TMP/Ups_1_" + toString(en + ix + 3), refData(3 * ih - 2, 1, 2 + ix));
    }
    for (size_t ix = 0; ix < 2; ++ix) { // decays to 2S
      for (size_t iy = 0; iy < 2; ++iy) {
        book(_h_pT_2S[en + ix + 2 * iy], "TMP/Ups_2_" + toString(en + ix + 2 * iy),
             refData(3 * ih - 1, 1, 2 + ix));
      }
    }
    for (size_t ix = 0; ix < 2; ++ix) { // decays to 3S
      book(_h_pT_3S[en + ix], "TMP/Ups_3_" + toString(en + ix), refData(3 * ih, 1, 3));
    }
  }
  raiseBeamErrorIf(_sqs == 0);
}


/// Perform the per-event analysis
void analyze(const Event& event) {

  // Final state of unstable particles to get particle spectra
  const UnstableParticles& ufs = apply<UnstableParticles>(event, "UFS");

  // first the upsilon states for the denominator
  for (const Particle& p :
       ufs.particles(Cuts::pid == 553 || Cuts::pid == 100553 || Cuts::pid == 200553)) {
    // rapidity cut
    double absrap = p.absrap();
    if (absrap < 2. || absrap > 4.5) continue;
    double xp = p.perp();
    if (p.pid() == 553) {
      for (size_t ix = 0; ix < 2; ++ix) {
        _h_pT_1S[_sqs + 3 + ix]->fill(xp);
      }
    }
    else if (p.pid() == 100553) {
      for (size_t ix = 0; ix < 2; ++ix) {
        _h_pT_2S[_sqs + 2 + ix]->fill(xp);
      }
    }
    else if (p.pid() == 200553) {
      _h_pT_3S[_sqs + 1]->fill(xp);
    }
  }
  // P states
  for (const Particle& p :
       ufs.particles(Cuts::pid == 10551 || Cuts::pid == 110551 || Cuts::pid == 210551
                     || Cuts::pid == 20553 || Cuts::pid == 120553 || Cuts::pid == 220553
                     || Cuts::pid == 555 || Cuts::pid == 100555 || Cuts::pid == 200555)) {
    Particle Upsilon;
    if (p.children()[0].pid() == 22 && p.children()[1].abspid() % 100000 == 553) {
      Upsilon = p.children()[1];
    }
    else if (p.children()[1].pid() == 22 && p.children()[0].abspid() % 100000 == 553) {
      Upsilon = p.children()[0];
    }
    else {
      continue;
    }
    double absrap = Upsilon.absrap();
    if (absrap < 2. || absrap > 4.5) continue;
    unsigned int iups = p.children()[0].pid() / 100000;
    unsigned int ichi = p.pid() / 100000;
    double xp = Upsilon.perp();
    if (iups == 0)
      _h_pT_1S[_sqs + ichi]->fill(xp);
    else if (iups == 1 && ichi > 0)
      _h_pT_2S[_sqs + ichi - 1]->fill(xp);
    else if (iups == 2 && ichi == 2)
      _h_pT_3S[_sqs + 0]->fill(xp);
  }
}


/// Normalise histograms etc., after the run
void finalize() {
  for (double eVal : allowedEnergies()) {
    const int en = int(eVal + 0.5);
    int ih = int(en == 8000) + 1;
    // calculate the ratios
    // for 1S
    for (size_t iy = 0; iy < 3; ++iy) {
      Estimate1DPtr tmp;
      book(tmp, 3 * ih - 2, 1, iy + 1);
      if (iy < 2)
        efficiency(_h_pT_1S[en + iy], _h_pT_1S[en + 3], tmp);
      else
        efficiency(_h_pT_1S[en + iy], _h_pT_1S[en + 4], tmp);
      tmp->scale(100.);
    }
    Estimate1DPtr tmp;
    book(tmp, 3 * ih - 1, 1, 2);
    efficiency(_h_pT_2S[en + 0], _h_pT_2S[en + 2], tmp);
    tmp->scale(100.);
    book(tmp, 3 * ih - 1, 1, 3);
    efficiency(_h_pT_2S[en + 1], _h_pT_2S[en + 3], tmp);
    tmp->scale(100.);
    book(tmp, 3 * ih, 1, 3);
    efficiency(_h_pT_3S[en + 0], _h_pT_3S[en + 1], tmp);
    tmp->scale(100.);
  }
}

/// @}


/// @name Histograms
/// @{
map<size_t, Histo1DPtr> _h_pT_1S, _h_pT_2S, _h_pT_3S;
int _sqs = 0;
/// @}

};

RIVET_DECLARE_PLUGIN(LHCB_2014_I1308738);

} ```