Rivet analyses

title: LHCB_2015_I1392456

Differential cross sections for $\Upsilon(1,2,3S)$ production at 7 and 8 TeV

Experiment: LHCB (LHC)

Inspire ID: 1392456

Status: VALIDATED

Authors: - Peter Richardson

References: - JHEP 11 (2015) 103

Beams: p+ p+

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

Run details: - hadronic events with Upsilon production

Measurement of the double differential (in $p_\perp$ and $y$) cross section for $\Upsilon(1,2,3S)$ production at 7 and 8 TeV by the LHCB collaboration.

Source code:LHCB_2015_I1392456.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {

/// @brief Upsilon production at 7,8 TeV class LHCB_2015_I1392456 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(LHCB_2015_I1392456);


/// @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 = en == 7000 ? 0 : 10;
    for (size_t iups = 0; iups < 3; ++iups) {
      book(_h_Ups[en + iups], {2.0, 2.5, 3.0, 3.5, 4.0, 4.5});
      for (size_t iy = 0; iy < 5; ++iy) {
        book(_h_Ups[en + iups]->bin(iy + 1), 1 + iups + ih, 1, 1 + iy);
      }
      book(_h_Ups_pT[en + iups], 4 + ih, 1, 1 + iups);
      book(_h_Ups_y[en + iups], 5 + ih, 1, 1 + iups);
    }
  }
  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");
  for (const Particle& p :
       ufs.particles(Cuts::pid == 553 or Cuts::pid == 100553 or Cuts::pid == 200553)) {
    const double absrap = p.absrap();
    const double xp = p.perp();
    if (absrap < 2.0 || absrap > 4.5) continue;
    unsigned int iups = p.pid() / 100000;
    _h_Ups_pT[_sqs + iups]->fill(xp);
    if (xp < 30.) _h_Ups_y[_sqs + iups]->fill(absrap);
    _h_Ups[_sqs + iups]->fill(absrap, xp);
  }
}


/// Normalise histograms etc., after the run
void finalize() {
  // 1/2 due rapidity folding +/-
  const double factor = 0.5 * crossSection() / picobarn / sumOfWeights();
  // branching ratios for upsilon
  vector<double> br = {0.0248, 0.0193, 0.0218};

  for (double eVal : allowedEnergies()) {
    const int en = int(eVal + 0.5);
    for (size_t iups = 0; iups < 3; ++iups) {
      scale(_h_Ups_pT[en + iups], factor * br[iups]);
      scale(_h_Ups_y[en + iups], factor / 1000. * br[iups]);
      scale(_h_Ups[en + iups], factor * br[iups]);
      divByGroupWidth(_h_Ups[en + iups]);
    }
    size_t ih = en == 8000 ? 10 : 0;
    for (size_t ix = 0; ix < _h_Ups[en + 0]->numBins(); ++ix) {
      Estimate1DPtr tmp;
      book(tmp, 6 + ih, 1, 1 + ix);
      divide(_h_Ups[en + 1]->bin(ix + 1), _h_Ups[en + 0]->bin(ix + 1), tmp);
      book(tmp, 7 + ih, 1, 1 + ix);
      divide(_h_Ups[en + 2]->bin(ix + 1), _h_Ups[en + 0]->bin(ix + 1), tmp);
      book(tmp, 8 + ih, 1, 1 + ix);
      divide(_h_Ups[en + 2]->bin(ix + 1), _h_Ups[en + 1]->bin(ix + 1), tmp);
    }
    for (size_t iups = 1; iups < 3; ++iups) {
      Estimate1DPtr tmp;
      book(tmp, 9 + ih, 1, iups);
      divide(_h_Ups_pT[en + iups], _h_Ups_pT[en + 0], tmp);
      book(tmp, 10 + ih, 1, iups);
      divide(_h_Ups_y[en + iups], _h_Ups_y[en + 0], tmp);
    }
    Estimate1DPtr tmp;
    book(tmp, 9 + ih, 1, 3);
    divide(_h_Ups_pT[en + 2], _h_Ups_pT[en + 1], tmp);
    book(tmp, 10 + ih, 1, 3);
    divide(_h_Ups_y[en + 2], _h_Ups_y[en + 1], tmp);
  }
}

/// @}


/// @name Histograms
/// @{
map<int, Histo1DPtr> _h_Ups_pT, _h_Ups_y;
map<int, Histo1DGroupPtr> _h_Ups;
int _sqs = 0;
/// @}

};

RIVET_DECLARE_PLUGIN(LHCB_2015_I1392456);

} ```