Rivet analyses

title: CLEOIII_2005_I675005

Hadronic mass spectra in four hadron $\tau^-$ decays with $K^\pm$

Experiment: CLEOIII (CESR)

Inspire ID: 675005

Status: VALIDATED NOHEPDATA

Authors: - Peter Richardson

References: - Phys.Rev.Lett. 94 (2005) 241802

Beams: * *

Beam energies: ANY

Run details: - Any process producting tau leptons, originally e+e-

Measurement of the hadronic mass spectrum in $\tau^-\to K^-\pi^+\pi^-\pi^0\nu_\tau$ (excluding $\omega$ and $K^-\omega\nu_\tau$) and $\tau^-\to K^-K^+\pi^-\pi^0\nu_\tau$ decays. The background subtracted, efficiency corrected data were read from Figure 2 in the paper.

Source code:CLEOIII_2005_I675005.cc

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

include "Rivet/Analysis.hh"

include "Rivet/Projections/DecayedParticles.hh"

include "Rivet/Projections/UnstableParticles.hh"

namespace Rivet {

/// @brief Hadronic mass spectra in four hadron tau- decays with K+/- class CLEOIII_2005_I675005 : public Analysis { public:

/// Constructor
RIVET_DEFAULT_ANALYSIS_CTOR(CLEOIII_2005_I675005);


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

/// Book histograms and initialise projections before the run
void init() {
  // Initialise and register projections
  UnstableParticles ufs = UnstableParticles(Cuts::abspid == 15);
  declare(ufs, "UFS");
  DecayedParticles TAU(ufs);
  TAU.addStable(310);
  TAU.addStable(223);
  TAU.addStable(111);
  declare(TAU, "TAU");
  // histos
  for (unsigned int ix = 0; ix < 3; ++ix) {
    book(_h[ix], 1, 1, 1 + ix);
  }
}


/// Perform the per-event analysis
void analyze(const Event& event) {
  DecayedParticles TAU = apply<DecayedParticles>(event, "TAU");
  // loop over particles
  for (unsigned int ix = 0; ix < TAU.decaying().size(); ++ix) {
    int sign = 1, imode = 0;
    if (TAU.decaying()[ix].pid() > 0 && TAU.modeMatches(ix, 5, mode1)) {
      sign = 1;
      imode = 0;
    }
    else if (TAU.decaying()[ix].pid() < 0 && TAU.modeMatches(ix, 5, mode1CC)) {
      sign = -1;
      imode = 0;
    }
    else if (TAU.decaying()[ix].pid() > 0 && TAU.modeMatches(ix, 3, mode2)) {
      sign = 1;
      imode = 1;
    }
    else if (TAU.decaying()[ix].pid() < 0 && TAU.modeMatches(ix, 3, mode2CC)) {
      sign = -1;
      imode = 1;
    }
    else if (TAU.decaying()[ix].pid() > 0 && TAU.modeMatches(ix, 5, mode3)) {
      sign = 1;
      imode = 2;
    }
    else if (TAU.decaying()[ix].pid() < 0 && TAU.modeMatches(ix, 5, mode3CC)) {
      sign = -1;
      imode = 2;
    }
    else {
      continue;
    }
    const Particle& nu = TAU.decayProducts()[ix].at(16 * sign)[0];
    const double mass = (TAU.decaying()[ix].mom() - nu.mom()).mass();
    _h[imode]->fill(mass);
  }
}


/// Normalise histograms etc., after the run
void finalize() {
  normalize(_h, 1.0, false);
}

/// @}


/// @name Histograms
/// @{
Histo1DPtr _h[3];
const map<PdgId, unsigned int> mode1 = {{-321, 1}, {211, 1}, {-211, 1}, {111, 1}, {16, 1}};
const map<PdgId, unsigned int> mode1CC = {{321, 1}, {211, 1}, {-211, 1}, {111, 1}, {-16, 1}};
const map<PdgId, unsigned int> mode2 = {{-321, 1}, {223, 1}, {16, 1}};
const map<PdgId, unsigned int> mode2CC = {{321, 1}, {223, 1}, {-16, 1}};
const map<PdgId, unsigned int> mode3 = {{321, 1}, {-321, 1}, {-211, 1}, {111, 1}, {16, 1}};
const map<PdgId, unsigned int> mode3CC = {{321, 1}, {-321, 1}, {211, 1}, {111, 1}, {-16, 1}};
/// @}

};

RIVET_DECLARE_PLUGIN(CLEOIII_2005_I675005);

} ```