AnalyticalCherenkovModel.h

Go to the documentation of this file.

#ifndef _atm_AnalyticalCherenkovModel_h_
#define _atm_AnalyticalCherenkovModel_h_


#include <atm/VCherenkovModel.h>
#include <atm/Arbeletche2021CherenkovAngularModel.h>
#include <utl/TabulatedFunction.h>
#include <utl/Point.h>


namespace utl {
  class TabulatedFunction;
}

namespace atm {

  class AnalyticalCherenkovModel : public atm::VCherenkovModel {

  public:
    AnalyticalCherenkovModel();
    virtual ~AnalyticalCherenkovModel() { }
    void Init();

    // Possible parametrizations for the Energy Electron Spectrum.
    enum Parametrization { eHillas, eGiller, eNerling };

    // Possible parametrizations for the Angular Electron Distribution.
    enum ParametrizationAngular { eAngHillas, eAngNerling, eAngGiller, eAngArbeletche };

    utl::TabulatedFunction&
    EvaluateCherenkovPhotons(const utl::Point& xA,
                             const utl::Point& xB,
                             const double showerAge) const;

    utl::TabulatedFunction&
    EvaluateCherenkovDirect(const utl::Point& xA,
                            const utl::Point& xB,
                            const utl::Point& xEye,
                            const double showerAge) const;
    double
    EvaluateDirectCherenkovProbability(const utl::Point& xA, const utl::Point& xB,
                                       const utl::Point& xEye, const double showerAge) const;

    double
    EvaluateDirectCherenkovProbability(const utl::Point& xA, const utl::Point& xB,
                                       const utl::Point& xEye, const double showerAge, const double wavelength) const;

    double AngularCDF(const double theta, const double verticalDepth,
                      const double showerAge) const;
    double AngularPDF(const double theta, const double verticalDepth,
                      const double showerAge) const;

    bool HasData() const {return true;};

    void SetEnergyCutoff(double ecut) const;

  private:
    static const double fdE;
    static const double fjMax;
    static const double fNerlingMinValidShowerAge;
    static const double fNerlingMaxValidShowerAge;

    mutable utl::TabulatedFunction fCherenkovPhotons;
    mutable utl::TabulatedFunction fDirectCherenkovPhotons;

    bool fWlRefrac;
    bool fLowENerling;

    bool CorrectCherenkovAsymmetry(double age, double theta) const;

    bool fCorrectCherenkovAsymmetry;
    double fCherenkovAsymmetryMinAge;
    double fCherenkovAsymmetryMaxAge;
    double fCherenkovAsymmetryMinAngle;
    double fCherenkovAsymmetryMaxAngle; 
    double fCherenkovAsymmetryMinA;
    double fCherenkovAsymmetryMaxA;

    std::vector<double> fWavelength;

    Parametrization fParam;
    ParametrizationAngular fParamAngular;

    double CherenkovTrackLength(double energy, double showerAge) const;

    double DeltaPhotons(double nIndex, double eelec,
                        double dSlant, double wl1, double wl2) const;

    double CherenkovIntegral(double lowAngle, double highAngle,
                             double meanShowerAge, double refractiveIndex) const;
    

    double AsymmCorrection(double a, double theta, double sinphi) const;

    double AsymmCorrection (const utl::Point& emissionPoint,
                            const utl::Vector& v_toeye,
                            const utl::Vector& axis,
                            double density) const;

    double AsymmCorrection (const utl::Point& xA,
                            const utl::Point& xB,
                            const utl::Point& xEye) const;


    double AsymmCorrectionOld (double bm, double bp, double sinphi) const;
    double AsymmCorrectionOld (const utl::Vector& v_toeye,
                               const utl::Vector& axis,
                               double density) const;

    const std::vector<double>& GetWavelengths() const
    { return fWavelength; }
    
    // Angular distribution of Cherenkov light parametrized by Arbeletche and de Souza
    // EPJC 81, p195, 2021 (10.1140/epjc/s10052-021-08971-7)
    // Used when option eAngArbeletche is set
    Arbeletche2021CherenkovAngularModel fArbeletcheAngularDistribution;

    mutable utl::Point fxAprevious;
    mutable utl::Point fxBprevious;
    mutable double fShowerAgePrevious;
    mutable std::vector<double> fNerlingFactor;

    REGISTER_MODEL(atm::VCherenkovModel, "Analytical",AnalyticalCherenkovModel);
  };

}


#endif

// Configure (x)emacs for this file ...
// Local Variables:
// mode: c++
// compile-command: "make -C .. -k"
// End: