RkFitMaterial Class Reference

#include <RkFitMaterial.h>

Public Member Functions
	RkFitMaterial ()
	Constructor.
	RkFitMaterial (double z, double a, double i, double rho, double x0)
	RkFitMaterial (const RkFitMaterial &mat)
double	dE (double mass, double path, double p) const
	Calculate energy loss.
double	mcs_angle (double mass, double path, double p) const
	Calculate Multiple Scattering angle.
double	del_E (double mass, double path, double p) const
	Calculate the straggling of energy loss.
double	X0 (void) const
	Extractor.
	RkFitMaterial ()
	Constructor.
	RkFitMaterial (double z, double a, double i, double rho, double x0)
	RkFitMaterial (const RkFitMaterial &mat)
double	dE (double mass, double path, double p) const
	Calculate energy loss.
double	mcs_angle (double mass, double path, double p) const
	Calculate Multiple Scattering angle.
double	del_E (double mass, double path, double p) const
	Calculate the straggling of energy loss.
double	X0 (void) const
	Extractor.

Detailed Description

Definition at line 6 of file InstallArea/include/TrkReco/TrkReco/RkFitMaterial.h.

Constructor & Destructor Documentation

RkFitMaterial() [1/6]

RkFitMaterial::RkFitMaterial ( )

inline

Constructor.

Definition at line 14 of file InstallArea/include/TrkReco/TrkReco/RkFitMaterial.h.

{}

RkFitMaterial() [2/6]

RkFitMaterial::RkFitMaterial	(	double	z,
		double	a,
		double	i,
		double	rho,
		double	x0
	)

Definition at line 18 of file RkFitMaterial.cxx.

  : x0_(x0), z_(z)  // rho is the density, z is the atomic number, a is the weight
                    // i is mean excitation potention, x0 is the radiation length
{
  rza_ = rho * z / a;
  isq_  = i * i * 1e-18;
}

RkFitMaterial() [3/6]

RkFitMaterial::RkFitMaterial

(

const RkFitMaterial &

mat

)

Definition at line 27 of file RkFitMaterial.cxx.

  : rza_(mat.rza_), isq_(mat.isq_),
    x0_(mat.x0_), z_(mat.z_)
{
   
}

RkFitMaterial() [4/6]

RkFitMaterial::RkFitMaterial ( )

inline

Constructor.

Definition at line 14 of file Reconstruction/TrkReco/TrkReco-00-08-59-patch4-slc6tag/TrkReco/RkFitMaterial.h.

{}

RkFitMaterial() [5/6]

RkFitMaterial::RkFitMaterial	(	double	z,
		double	a,
		double	i,
		double	rho,
		double	x0
	)

RkFitMaterial() [6/6]

RkFitMaterial::RkFitMaterial

(

const RkFitMaterial &

mat

)

Member Function Documentation

dE() [1/2]

double RkFitMaterial::dE	(	double	mass,
		double	path,
		double	p
	)		const

Calculate energy loss.

Definition at line 35 of file RkFitMaterial.cxx.

{
  if (!(p>0))
    return 0;
 
  //cout<<"this material:x0 "<< x0_ << " Z  " << z_ << endl
  //    <<"  rho*Z/A  "<< rza_ << " I^2 "<< isq_ << endl;
 
  const double Me = 0.000510999;
  double psq = p * p;
  double bsq = psq / (psq + mass * mass);
  double esq = psq / (mass * mass);
 
  double s = Me / mass;
  double w = (4 * Me * esq
          / (1 + 2 * s * sqrt(1 + esq)
         + s * s));
  // Density correction :
  double cc, x0;
  cc = 1+2*log(sqrt(isq_)/(28.8E-09*sqrt(rza_)));
  if (cc < 5.215) 
    x0 = 0.2;
  else
    x0 = 0.326*cc-1.5;
  double x1(3), xa(cc/4.606), aa;
  aa = 4.606*(xa-x0)/((x1-x0)*(x1-x0)*(x1-x0));
  double delta(0);
  double x(log10(sqrt(esq)));
  if (x > x0){    
    delta = 4.606*x-cc;
    if (x < x1) delta=delta+aa*(x1-x)*(x1-x)*(x1-x);
  }
 // Shell correction :  
  float f1, f2, f3, f4, f5, ce;
  f1 = 1/esq;
  f2 = f1*f1;
  f3 = f1*f2;
  f4 = (f1*0.42237+f2*0.0304-f3*0.00038)*1E12;
  f5 = (f1*3.858-f2*0.1668+f3*0.00158)*1E18;
  ce = f4*isq_+f5*isq_*sqrt(isq_);
  return (0.0001535 * rza_ / bsq
      * (log(Me * esq * w / isq_)
         - 2 * bsq-delta-2.0*ce/z_)) * path;
}

Referenced by TRunge::eloss().

dE() [2/2]

double RkFitMaterial::dE	(	double	mass,
		double	path,
		double	p
	)		const

Calculate energy loss.

del_E() [1/2]

double RkFitMaterial::del_E	(	double	mass,
		double	path,
		double	p
	)		const

Calculate the straggling of energy loss.

Definition at line 95 of file RkFitMaterial.cxx.

{
  double sigma0_2 = 0.1569*rza_*path;
 
  if (sigma0_2<0) return 0;
 
  double psq = p * p;
  double bsq = psq / (psq + mass * mass);
 
  // Correction for relativistic particles :
  double sigma_2 = sigma0_2*(1-0.5*bsq)/(1-bsq);
 
  if (sigma_2<0) return 0;
 
  // Return sigma in GeV !!
  return sqrt(sigma_2)*0.001;
 
}

del_E() [2/2]

double RkFitMaterial::del_E	(	double	mass,
		double	path,
		double	p
	)		const

Calculate the straggling of energy loss.

mcs_angle() [1/2]

double RkFitMaterial::mcs_angle	(	double	mass,
		double	path,
		double	p
	)		const

Calculate Multiple Scattering angle.

Definition at line 83 of file RkFitMaterial.cxx.

{
  //cout<<"this material:x0 "<< x0_ << " Z  " << z_ << endl
  //    <<"  rho*Z/A  "<< rza_ << " I^2 "<< isq_ << endl;
  double t = path / x0_;
  double psq = p*p;
  return 0.0136 * sqrt(t * (mass*mass + psq)) / psq
    * (1 + 0.038 * log(t));
}

mcs_angle() [2/2]

double RkFitMaterial::mcs_angle	(	double	mass,
		double	path,
		double	p
	)		const

Calculate Multiple Scattering angle.

X0() [1/2]

double RkFitMaterial::X0 ( void  ) const

inline

Extractor.

Definition at line 28 of file InstallArea/include/TrkReco/TrkReco/RkFitMaterial.h.

{ return x0_; }

X0() [2/2]

double RkFitMaterial::X0 ( void  ) const

inline

Extractor.

Definition at line 28 of file Reconstruction/TrkReco/TrkReco-00-08-59-patch4-slc6tag/TrkReco/RkFitMaterial.h.

{ return x0_; }

---

The documentation for this class was generated from the following files:

• InstallArea/include/TrkReco/TrkReco/RkFitMaterial.h
• Reconstruction/TrkReco/TrkReco-00-08-59-patch4-slc6tag/TrkReco/RkFitMaterial.h
• RkFitMaterial.cxx