Rivet Analyses Reference

ALICE_2011_S8909580

Strange particle production in proton-proton collisions at $\sqrt{s} = 0.9$ TeV with ALICE at the LHC.
Experiment: ALICE (LHC)
Inspire ID: 881474
Status: VALIDATED
Authors:
  • Pablo Bueno Gomez
  • Eva Sicking
References:
  • Eur.Phys.J.C71:1594,2011.
Beams: p+ p+
Beam energies: (450.0, 450.0) GeV
Run details:
  • Diffractive events need to be switched on.

Transverse momentum spectra of strange particles ($K^0_S$, $\Lambda$, $\phi$ and $\Xi$) in $pp$ collisions at $\sqrt{s} = 0.9$ TeV with ALICE at the LHC. The ratio of cross-sections as a function of pT for $\Lambda/K^0_S$ is also included.

Source code: ALICE_2011_S8909580.cc
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#include "Rivet/Analysis.hh"
#include "Rivet/Projections/FinalState.hh"
#include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {


  class ALICE_2011_S8909580 : public Analysis {
  public:

    RIVET_DEFAULT_ANALYSIS_CTOR(ALICE_2011_S8909580);


    void init() {
      const UnstableParticles ufs(Cuts::abseta < 15);
      declare(ufs, "UFS");

      book(_histPtK0s        ,1, 1, 1);
      book(_histPtLambda     ,2, 1, 1);
      book(_histPtAntiLambda ,3, 1, 1);
      book(_histPtXi         ,4, 1, 1);
      book(_histPtPhi        ,5, 1, 1);
      book(_temp_h_Lambdas   ,"TMP/h_Lambdas", refData(6, 1, 1));
      book(_temp_h_Kzeros    ,"TMP/h_Kzeros", refData(6, 1, 1));
      book(_h_LamKzero       ,6, 1, 1);
    }


    void analyze(const Event& event) {
      const UnstableParticles& ufs = apply<UnstableParticles>(event, "UFS");

      for (const Particle& p : ufs.particles()) {
        const double absrap = p.absrap();
        const double pT = p.pT()/GeV;

        if (absrap < 0.8) {
          switch(p.pid()) {
          case 3312:
          case -3312:
            if ( !( p.hasAncestor(3334) || p.hasAncestor(-3334) ) ) {
              _histPtXi->fill(pT);
            }
            break;
            if (absrap < 0.75) {
            case 310:
              _histPtK0s->fill(pT);
              _temp_h_Kzeros->fill(pT, 2);
              break;
            case 3122:
              if ( !( p.hasAncestor(3322) || p.hasAncestor(-3322) ||
                      p.hasAncestor(3312) || p.hasAncestor(-3312) ||
                      p.hasAncestor(3334) || p.hasAncestor(-3334) ) ) {
                _histPtLambda->fill(pT);
                _temp_h_Lambdas->fill(pT);
              }
              break;
            case -3122:
              if ( !( p.hasAncestor(3322) || p.hasAncestor(-3322) ||
                      p.hasAncestor(3312) || p.hasAncestor(-3312) ||
                      p.hasAncestor(3334) || p.hasAncestor(-3334) ) ) {
                _histPtAntiLambda->fill(pT);
                _temp_h_Lambdas->fill(pT);
              }
              break;
            }
            if (absrap<0.6) {
            case 333:
              _histPtPhi->fill(pT);
              break;
            }
          }
        }
      }
    }


    void finalize() {
      scale(_histPtK0s,        1./(1.5*sumOfWeights()));
      scale(_histPtLambda,     1./(1.5*sumOfWeights()));
      scale(_histPtAntiLambda, 1./(1.5*sumOfWeights()));
      scale(_histPtXi,         1./(1.6*sumOfWeights()));
      scale(_histPtPhi,        1./(1.2*sumOfWeights()));
      divide(_temp_h_Lambdas, _temp_h_Kzeros, _h_LamKzero);
    }


  private:

    Histo1DPtr _histPtK0s, _histPtLambda, _histPtAntiLambda, _histPtXi, _histPtPhi;
    Histo1DPtr _temp_h_Lambdas, _temp_h_Kzeros;
    Scatter2DPtr _h_LamKzero;

  };


  RIVET_DECLARE_ALIASED_PLUGIN(ALICE_2011_S8909580, ALICE_2011_I881474);

}