LDFFinderKG/NKGLDF.h

Go to the documentation of this file.

#ifndef _LDFFinderKG_NKGLDF_h_
#define _LDFFinderKG_NKGLDF_h_


#include "VLDF.h"
#include <cmath>
#include <vector>
#include <utl/Math.h>
#include <utl/AugerUnits.h>


namespace LDFFinderKG {

  class NKGLDF : public VLDF {

  public:
    NKGLDF(const double refDistance) : VLDF(refDistance, 18, 2) { }

  protected:
    NKGLDF(const double refDistance, const unsigned int shapeSize) : VLDF(refDistance, shapeSize, 2) { }

    const double k700  = 700*utl::meter;

  public:
    double
    Value(const double r, const std::vector<double>& shape)
      const
    {
      const double rRef  = fReferenceDistance;
      const double beta  = shape[0];
      const double gamma = shape[1];

      return std::pow(r/rRef, beta) *
        std::pow((r + k700)/(rRef + k700), beta+gamma);
    }

    double
    SecondDerivative(const double r, const std::vector<double>& shape)
      const
    {
      const double beta = shape[0];
      const double gamma = shape[1];

      const double tbg = 2*beta + gamma;
      const double r2 = utl::Sqr(r);
      return Value(r, shape) * (
        utl::Sqr(k700)*beta*(beta - 1) +
        (tbg - 1)*(2*k700*beta*r + tbg*r2)
      ) / (r2 * utl::Sqr(r+k700));
    }

    std::vector<double>
    ShapeModel(const double cosTheta, const double showerSize)
      const
    {
      std::vector<double> shape(2);

      double& beta = shape[0];
      const double lgS = std::log10(showerSize);
      const double sec = 1 / cosTheta;
      const double a0 = fShapeModelVector[0];
      const double a1 = fShapeModelVector[1];
      const double b0 = fShapeModelVector[2];
      const double b1 = fShapeModelVector[3];
      const double c0 = fShapeModelVector[4];
      const double c1 = fShapeModelVector[5];
      beta = a0 + a1*lgS + sec*(b0 + b1*lgS + sec*(c0 + c1*lgS));

      double& gamma = shape[1];
      const double cos2 = utl::Sqr(cosTheta);
      const double fo0 = fShapeModelVector[6];
      const double fo1 = fShapeModelVector[7];
      const double fa0 = fShapeModelVector[8];
      const double fa1 = fShapeModelVector[9];
      const double fp0 = fShapeModelVector[10];
      const double fp1 = fShapeModelVector[11];
      const double fs0 = fShapeModelVector[12];
      const double fs1 = fShapeModelVector[13];
      const double fb  = fShapeModelVector[14];
      const double fet = fShapeModelVector[15];
      const double fps = fShapeModelVector[16];
      const double fss = fShapeModelVector[17];
      gamma =
        fo0 + fo1 * lgS +
        (fa0 + fa1 * lgS) / (std::exp((fs0 + fs1 * lgS) * (cos2 - (fp0 + fp1 * lgS))) + 1) +
        fb * std::pow(cos2, fet) / (std::exp((lgS - fps) * fss) + 1) -
        beta; // define as modification of exponent on second term for backwards compatibility

      return shape;
    }

    double
    BetaUncertainty(const double showerSize)
      const
    {
      const double lgS = std::log10(showerSize);
      return fBetaUncertaintyModelVector[0] * exp(fBetaUncertaintyModelVector[1] * lgS);
    }

    unsigned int GetNShapeParameters() const { return 2; }

  };

}


#endif