FastSimulation/MaterialEffects/interface/MuonBremsstrahlungSimulator.h - master - githubmirror/cmssw

FastSimulation/MaterialEffects/interface/MuonBremsstrahlungSimulator.h
76 строк2 KB
Kevin Pedro
fix potential memory leaks
06 дек 2025, 00:42
06 дек 2025, 00:42e22405e
#ifndef MUONBREMSSTRAHLUNGSIMULATOR_H
#define MUONBREMSSTRAHLUNGSIMULATOR_H

#include "FastSimulation/MaterialEffects/interface/MaterialEffectsSimulator.h"

/** 
 * This class computes the number, energy and angles of Bremsstrahlung 
 * photons emitted by electrons and positrons (under the form of a 
 * ParticlePropagator, i.e., a RawParticle) in the tracker layer, 
 * and returns the RawParticle modified after radiation as well as 
 * a list of photons (i.e., a list of RawParticles as well).
 * The fraction of radiation lengths traversed by the particle 
 * in this tracker layer is determined in MaterialEffectsSimulator.
 *
 * This version (a la PDG) of a dE/dx generator replaces the buggy 
 * GEANT3 Fortran -> C++ former version (up to FAMOS_0_8_0_pre7).
 *
 * \author Patrick Janot
 * $Date: 25-Dec-2003
 */

#include "TF1.h"

#include <string>

class ParticlePropagator;
class RandomEngineAndDistribution;

class MuonBremsstrahlungSimulator : public MaterialEffectsSimulator {
public:
  /// Constructor
  MuonBremsstrahlungSimulator(
      double A, double Z, double density, double radLen, double photonEnergyCut, double photonFractECut);

  /// Default destructor
  ~MuonBremsstrahlungSimulator() override {}

  // Returns the actual Muon brem Energy
  inline const XYZTLorentzVector& deltaP_BremMuon() const { return deltaPMuon; }

  // Returns the actual photon brem Energy
  inline const XYZTLorentzVector& deltaP_BremPhoton() const { return brem_photon; }

private:
  std::unique_ptr<TF1> f1;

  int npar;

  /// The minimum photon energy to be radiated, in GeV
  double photonEnergy;
  double bremProba;
  /// The minimum photon fractional energy (wrt that of the electron)
  double photonFractE;

  /// The fractional photon energy cut (determined from the above two)
  double xmin, xmax, rand;
  double d;  //distance

  /// Generate numbers according to a Poisson distribution of mean ymu.
  unsigned int poisson(double ymu);

  /// Generate Bremsstrahlung photons
  void compute(ParticlePropagator& Particle, RandomEngineAndDistribution const*) override;

  /// Compute Brem photon energy and angles, if any.
  XYZTLorentzVector brem(ParticlePropagator& p, RandomEngineAndDistribution const*) const;

  /// A universal angular distribution - still from GEANT.
  double gbteth(const double ener, const double partm, const double efrac, RandomEngineAndDistribution const*) const;

  // The actual Muon Brem
  XYZTLorentzVector deltaPMuon;
  //The photon brem
  XYZTLorentzVector brem_photon;
};
#endif