CbmStsRadTool.h

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/** @file CbmStsRadTool.h
 ** @author Volker Friese <v.friese@gsi.de>
 ** @date 6 December 2011
 **/
 
#ifndef CBMSTSRADTOOL_H
#define CBMSTSRADTOOL_H 1
 
#include "TObject.h"
 
#include <map>
 
using namespace std;
 
/** @class CbmStsRadTool
 ** @author Volker Friese <v.friese@gsi.de>
 ** @date 6 December 2011
 ** @brief Tool class to calculate the non-ionising radiation damage
 ** on the STS silicon
 **
 ** This class provides some functionality to calculate the effects
 ** of non-ionising irradiation on Silicon.
 **
 ** While the calculation of the NIEL factor is independent of the
 ** type of silicon used, those of leakage current and full depletion
 ** voltage depend on the specific silicon properties (effective
 ** doping concentration 9 x 10^11 cm^-3).
 **/
class CbmStsRadTool : public TObject
{
 
  public:
    /**   Constructor   **/
    CbmStsRadTool();
 
    /**   Destructor   **/
    virtual ~CbmStsRadTool();
 
    /** Get leakage current
     ** @param[in] fluence       Fluence [neq/cm^2]
     ** @param[in] volume        Volume [cm^3]
     ** @param[in] temperature   Temperature [K]
     ** @return    Leakage current [A]
     **
     ** Calculates the leakage current in Silicon as function of irradiation
     ** fluence, volume and temperature.
     **
     ** Formulae provided by S. Chatterji.
     **/
    Double_t GetLeakageCurrent(Double_t fluence, Double_t volume, Double_t temperature);
 
    /**  Get NIEL factor
     *@param type   Particle Id (PDG code)
     *@param energy Energy in GeV
     *@return NIEL factor
     **
     ** Calculates the NIEL factor for a given particle type and energy
     ** from interpolation of the values tabulated in
     ** http://sesam.desy.de/members/gunnar/Si-dfuncs.htm
     **
     ** Will return 0 for particle types other than proton, neutron,
     ** pion or electron, or if the energy is below the lowest tabulated
     ** value. Will return an asymptotic value if the energy is above the
     ** highest tabulated value.
     **/
    Double_t GetNiel(Int_t type, Double_t energy);
 
    /** Get full depletion voltage
     ** @param fluence  Fluence [neq/cm^2]
     ** @param d        Thickness [cm]
     ** @return Full depletion voltage [V]
     **
     ** Calculates the full depletion voltage of Silicon as function of
     ** non-ionising dose and thickness.
     **
     ** Formulae and values provided by S. Chatterji.
     **/
    Double_t GetVfd(Double_t fluence, Double_t d);
 
  private:
    /** Tables of NIEL factors as fnct. of energy **/
    map<Double_t, Double_t> niel_neutron;
    map<Double_t, Double_t> niel_proton;
    map<Double_t, Double_t> niel_pion;
    map<Double_t, Double_t> niel_electron;
 
    /** Proportionality constant of leakage current and fluence **/
    Double_t fIAlpha;   //  [A/cm]
 
    /** Constants for temperature dependence of leakage current **/
    Double_t fEGap0;       // [eV]
    Double_t fEGapAlpha;   // [ev?k]
    Double_t fEGapBeta;    // [K]
 
    /** Constants for effective doping concentration
     ** as function of fluence
     **/
    Double_t fNeff0;    // [cm^-3]
    Double_t fNeffC;    // [cm^2]
    Double_t fNeffGc;   // [1/cm]
 
    /** Permittivity of Silicon **/
    Double_t fEpsilon;   // [F/cm]
 
    /** Initialisation
     **
     ** Reads in tabulated NIEL factors from file
     ** and sets proper constants for Silicon.
     **/
    void Init();
 
    /** Read data from file
     *@param file  File name (in directory input)
     *@param map   Map to be filled
     **/
    void ReadData(const char* file, map<Double_t, Double_t>& map);
 
    ClassDef(CbmStsRadTool, 1);
};
 
#endif