- return m/fdv; // [cm/sec]
-}
-//______________________________________________________________________
-Double_t AliITSCalibration::SpeedHole() const {
- // Computes the average speed for Holes in Si under the low-field
- // approximation.[cm/sec].
- // Inputs:
- // none.
- // Output:
- // none.
- // Return:
- // The speed the holes are traveling at due to the low field applied.
- // [cm/sec]
- Double_t m = MobilityHoleSiEmp();
-
- return m/fdv; // [cm/sec]
-}
-//______________________________________________________________________
-Double_t AliITSCalibration::SigmaDiffusion3D(Double_t l) const {
- // Returns the Gaussian sigma^2 == <x^2+y^2+z^2> [cm^2] due to the
- // defusion of electrons or holes through a distance l [cm] caused
- // by an applied voltage v [volt] through a distance d [cm] in any
- // material at a temperature T [degree K]. The sigma diffusion when
- // expressed in terms of the distance over which the diffusion
- // occures, l=time/speed, is independent of the mobility and therefore
- // the properties of the material. The charge distributions is given by
- // n = exp(-r^2/4Dt)/(4piDt)^1.5. From this <r^2> = 6Dt where D=mkT/e
- // (m==mobility, k==Boltzman's constant, T==temparature, e==electric
- // charge. and vel=m*v/d. consiquently sigma^2=6kTdl/ev.
- // Inputs:
- // Double_t l Distance the charge has to travel.
- // Output:
- // none.
- // Return:
- // The Sigma due to the diffution of electrons. [cm]
- const Double_t kcon = 5.17040258E-04; // == 6k/e [J/col or volts]
-
- return TMath::Sqrt(kcon*fT*fdv*l); // [cm]
-}
-//______________________________________________________________________
-Double_t AliITSCalibration::SigmaDiffusion2D(Double_t l) const {
- // Returns the Gaussian sigma^2 == <x^2+z^2> [cm^2] due to the defusion
- // of electrons or holes through a distance l [cm] caused by an applied
- // voltage v [volt] through a distance d [cm] in any material at a
- // temperature T [degree K]. The sigma diffusion when expressed in terms
- // of the distance over which the diffusion occures, l=time/speed, is
- // independent of the mobility and therefore the properties of the
- // material. The charge distributions is given by
- // n = exp(-r^2/4Dt)/(4piDt)^1.5. From this <x^2+z^2> = 4Dt where D=mkT/e
- // (m==mobility, k==Boltzman's constant, T==temparature, e==electric
- // charge. and vel=m*v/d. consiquently sigma^2=4kTdl/ev.
- // Inputs:
- // Double_t l Distance the charge has to travel.
- // Output:
- // none.
- // Return:
- // The Sigma due to the diffution of electrons. [cm]
- const Double_t kcon = 3.446935053E-04; // == 4k/e [J/col or volts]
-
- return TMath::Sqrt(kcon*fT*fdv*l); // [cm]
-}
-//______________________________________________________________________
-Double_t AliITSCalibration::SigmaDiffusion1D(Double_t l) const {
- // Returns the Gaussian sigma^2 == <x^2> [cm^2] due to the defusion
- // of electrons or holes through a distance l [cm] caused by an applied
- // voltage v [volt] through a distance d [cm] in any material at a
- // temperature T [degree K]. The sigma diffusion when expressed in terms
- // of the distance over which the diffusion occures, l=time/speed, is
- // independent of the mobility and therefore the properties of the
- // material. The charge distributions is given by
- // n = exp(-r^2/4Dt)/(4piDt)^1.5. From this <r^2> = 2Dt where D=mkT/e
- // (m==mobility, k==Boltzman's constant, T==temparature, e==electric
- // charge. and vel=m*v/d. consiquently sigma^2=2kTdl/ev.
- // Inputs:
- // Double_t l Distance the charge has to travel.
- // Output:
- // none.
- // Return:
- // The Sigma due to the diffution of electrons. [cm]
- const Double_t kcon = 1.723467527E-04; // == 2k/e [J/col or volts]
-
- return TMath::Sqrt(kcon*fT*fdv*l); // [cm]
-}
-//----------------------------------------------------------------------
-Double_t AliITSCalibration::DepletedRegionThicknessA(Double_t dopCons,
- Double_t voltage,
- Double_t elecCharge,
- Double_t voltBuiltIn)const{
- // Computes the thickness of the depleted region in Si due to the
- // application of an external bias voltage. From the Particle Data
- // Book, 28.8 Silicon semiconductor detectors equation 28.19 (2004)
- // Physics Letters B "Review of Particle Physics" Volume 592, Issue 1-4
- // July 15 2004, ISSN 0370-2693 page 263. First equation.
- // Inputs:
- // Double_t dopCons "N" doping concentration
- // Double_t voltage "V" external bias voltage
- // Double_t elecCharge "e" electronic charge
- // Double_t voltBuiltIn=0.5 "V_bi" "built-in" Voltage (~0.5V for
- // resistivities typically used in detectors)
- // Output:
- // none.
- // Return:
- // The thickness of the depleted region
-
- return TMath::Sqrt(2.0*(voltage+voltBuiltIn)/(dopCons*elecCharge));
-}
-//----------------------------------------------------------------------
-Double_t AliITSCalibration::DepletedRegionThicknessB(Double_t resist,
- Double_t voltage,
- Double_t mobility,
- Double_t voltBuiltIn,
- Double_t dielConst)const{
- // Computes the thickness of the depleted region in Si due to the
- // application of an external bias voltage. From the Particle Data
- // Book, 28.8 Silicon semiconductor detectors equation 28.19 (2004)
- // Physics Letters B "Review of Particle Physics" Volume 592, Issue 1-4
- // July 15 2004, ISSN 0370-2693 page 263. Second Equation.
- // Inputs:
- // Double_t resist "rho" resistivity (typically 1-10 kOhm cm)
- // Double_t voltage "V" external bias voltage
- // Double_t mobility "mu" charge carrier mobility
- // (electons 1350, holes 450 cm^2/V/s)
- // Double_t voltBuiltIn=0.5 "V_bi" "built-in" Voltage (~0.5V for
- // resistivities typically used in detectors)
- // Double_t dielConst=1.E-12 "epsilon" dielectric constant = 11.9 *
- // (permittivity of free space) or ~ 1 pF/cm
- // Output:
- // none.
- // Return:
- // The thickness of the depleted region
-
- return TMath::Sqrt(2.8*resist*mobility*dielConst*(voltage+voltBuiltIn));
-}
-//----------------------------------------------------------------------
-Double_t AliITSCalibration::ReverseBiasCurrent(Double_t temp,
- Double_t revBiasCurT1,
- Double_t tempT1,
- Double_t energy)const{
- // Computes the temperature dependance of the reverse bias current
- // of Si detectors. From the Particle Data
- // Book, 28.8 Silicon semiconductor detectors equation 28.21 (2004)
- // Physics Letters B "Review of Particle Physics" Volume 592, Issue 1-4
- // July 15 2004, ISSN 0370-2693 page 263.
- // Inputs:
- // Double_t temp The temperature at which the current is wanted
- // Double_t revBiasCurT1 The reference bias current at temp T1
- // Double_t tempT1 The temperature correstponding to revBiasCurT1
- // Double_t energy=1.2 Some energy [eV]
- // Output:
- // none.
- // Return:
- // The reverse bias current at the tempeature temp.
- const Double_t kBoltz = 8.617343E-5; //[eV/K]