genie::mueloss::BetheBlochModel Class Reference

Bethe-Bloch model for muon energy loss due to Ionization Concrete implementation of the MuELossI interface. More...

#include <BetheBlochModel.h>

Inheritance diagram for genie::mueloss::BetheBlochModel:

Public Member Functions
	BetheBlochModel ()
	BetheBlochModel (string config)
virtual	~BetheBlochModel ()
double	dE_dx (double E, MuELMaterial_t material) const
	implement the MuELossI interface More...
MuELProcess_t	Process (void) const
Public Member Functions inherited from genie::mueloss::MuELossI
virtual	~MuELossI ()
Public Member Functions inherited from genie::Algorithm
virtual	~Algorithm ()
virtual void	Configure (const Registry &config)
virtual void	Configure (string config)
virtual void	FindConfig (void)
virtual const Registry &	GetConfig (void) const
Registry *	GetOwnedConfig (void)
virtual const AlgId &	Id (void) const
	Get algorithm ID. More...
virtual AlgStatus_t	GetStatus (void) const
	Get algorithm status. More...
virtual bool	AllowReconfig (void) const
virtual AlgCmp_t	Compare (const Algorithm *alg) const
	Compare with input algorithm. More...
virtual void	SetId (const AlgId &id)
	Set algorithm ID. More...
virtual void	SetId (string name, string config)
const Algorithm *	SubAlg (const RgKey &registry_key) const
void	AdoptConfig (void)
void	AdoptSubstructure (void)
virtual void	Print (ostream &stream) const
	Print algorithm info. More...

Additional Inherited Members
Static Public Member Functions inherited from genie::Algorithm
static string	BuildParamVectKey (const std::string &comm_name, unsigned int i)
static string	BuildParamVectSizeKey (const std::string &comm_name)
Protected Member Functions inherited from genie::mueloss::MuELossI
	MuELossI ()
	MuELossI (string name)
	MuELossI (string name, string config)
Protected Member Functions inherited from genie::Algorithm
	Algorithm ()
	Algorithm (string name)
	Algorithm (string name, string config)
void	Initialize (void)
void	DeleteConfig (void)
void	DeleteSubstructure (void)
Registry *	ExtractLocalConfig (const Registry &in) const
Registry *	ExtractLowerConfig (const Registry &in, const string &alg_key) const
	Split an incoming configuration Registry into a block valid for the sub-algo identified by alg_key. More...
template<class T >
bool	GetParam (const RgKey &name, T &p, bool is_top_call=true) const
template<class T >
bool	GetParamDef (const RgKey &name, T &p, const T &def) const
template<class T >
int	GetParamVect (const std::string &comm_name, std::vector< T > &v, bool is_top_call=true) const
	Handle to load vectors of parameters. More...
int	GetParamVectKeys (const std::string &comm_name, std::vector< RgKey > &k, bool is_top_call=true) const
int	AddTopRegistry (Registry *rp, bool owns=true)
	add registry with top priority, also update ownership More...
int	AddLowRegistry (Registry *rp, bool owns=true)
	add registry with lowest priority, also update ownership More...
int	MergeTopRegistry (const Registry &r)
int	AddTopRegisties (const vector< Registry * > &rs, bool owns=false)
	Add registries with top priority, also udated Ownerships. More...
Protected Attributes inherited from genie::Algorithm
bool	fAllowReconfig
bool	fOwnsSubstruc
	true if it owns its substructure (sub-algs,...) More...
AlgId	fID
	algorithm name and configuration set More...
vector< Registry * >	fConfVect
vector< bool >	fOwnerships
	ownership for every registry in fConfVect More...
AlgStatus_t	fStatus
	algorithm execution status More...
AlgMap *	fOwnedSubAlgMp
	local pool for owned sub-algs (taken out of the factory pool) More...

Detailed Description

Bethe-Bloch model for muon energy loss due to Ionization Concrete implementation of the MuELossI interface.

W.Lohmann, R.Kopp and R.Voss, Energy Loss of Muons in the Energy Range 1-10000 GeV, CERN 85-03

Author

Costas Andreopoulos <constantinos.andreopoulos cern.ch> University of Liverpool & STFC Rutherford Appleton Laboratory

December 10, 2003

Copyright (c) 2003-2020, The GENIE Collaboration For the full text of the license visit http://copyright.genie-mc.org

Definition at line 30 of file BetheBlochModel.h.

Constructor & Destructor Documentation

BetheBlochModel::BetheBlochModel

(

)

Definition at line 22 of file BetheBlochModel.cxx.

                                 :
MuELossI("genie::mueloss::BetheBlochModel")
{

}

BetheBlochModel::BetheBlochModel

(

string

config

)

Definition at line 28 of file BetheBlochModel.cxx.

                                              :
MuELossI("genie::mueloss::BetheBlochModel", config)
{

}

BetheBlochModel::~BetheBlochModel ( )

virtual

Definition at line 34 of file BetheBlochModel.cxx.

{

}

Member Function Documentation

double BetheBlochModel::dE_dx ( double  E, MuELMaterial_t  material  ) const

virtual

implement the MuELossI interface

Implements genie::mueloss::MuELossI.

Definition at line 39 of file BetheBlochModel.cxx.

{
// Calculates ionization dE/dx for muons via Bethe-Bloch formula (in GeV^-2)
// To convert the result to more handly units, eg MeV/(gr/cm^2), just write:
// dE_dx /= (units::MeV/(units::g/units::cm2));

   if(mt == eMuUndefined) return 0;
   if(E<=MuELProcess::Threshold(this->Process()) || E>=kMaxMuE) return 0;

   double Z       = MuELMaterial::Z(mt);
   double A       = MuELMaterial::A(mt);
   double Z_A     = Z/A;              // in mol/gr
   double a2      = kAem2;            // (em coupling const)^2
   double Na      = kNA;              // Avogadro's number
   double lamda2 =  kLe2/units::cm2;  // (e compton wavelength)^2 in cm^2
   double me      = kElectronMass;    // in GeV
   double me2     = kElectronMass2;
   double mmu     = kMuonMass;        // in GeV
   double mmu2    = kMuonMass2;
   double E2      = TMath::Power(E,2);
   double beta    = TMath::Sqrt(E2-mmu2)/E;
   double beta2   = TMath::Power(beta,2);
   double gamma   = E/mmu;
   double gamma2  = TMath::Power(gamma,2);
   double I       = BetheBlochMaterialParams::IonizationPotential(mt) * units::eV;
   double I2      = TMath::Power(I,2); // in GeV^2

   // Calculate the maximum energy transfer to the electron (in GeV)

   double p2      = E2-mmu2;
   double Emaxt   = 2*me*p2 / (me2 + mmu2 + 2*me*E);
   double Emaxt2  = TMath::Power(Emaxt,2);

   // Calculate the density correction factor delta

   double X0 =  BetheBlochMaterialParams::DensityCorrection_X0(mt);
   double X1 =  BetheBlochMaterialParams::DensityCorrection_X1(mt);
   double a  =  BetheBlochMaterialParams::DensityCorrection_a(mt);
   double m  =  BetheBlochMaterialParams::DensityCorrection_m(mt);
   double C  =  BetheBlochMaterialParams::DensityCorrection_C(mt);
   double X  =  TMath::Log10(beta*gamma);

   double delta = 0;
   if(X0<X && X<X1) delta = 4.6052*X + a*TMath::Power(X1-X,m) + C;
   if(X>X1)         delta = 4.6052*X + C;

   LOG("MuELoss", pDEBUG) << "density correction factor = " << delta;
   LOG("MuELoss", pDEBUG) << "max energy transfer (GeV) = " << Emaxt;
   LOG("MuELoss", pDEBUG) << "ionization potential (GeV)= " << I;
   LOG("MuELoss", pDEBUG) << "E = " << E << ", p2 = " << p2;
   LOG("MuELoss", pDEBUG) << "beta = " << beta << ", gamma = " << gamma;

   // Calculate the -dE/dx
   double de_dx =  a2 * (2*kPi*Na*lamda2) * Z_A * (me/beta2) *
                    (TMath::Log( 2*me*beta2*gamma2*Emaxt/I2 ) -
                                      2*beta2 + 0.25*(Emaxt2/E2) - delta);

   de_dx *= (units::GeV/(units::g/units::cm2));
   return de_dx; // in GeV^-2
}

MuELProcess_t genie::mueloss::BetheBlochModel::Process ( void  ) const

inlinevirtual

Implements genie::mueloss::MuELossI.

Definition at line 39 of file BetheBlochModel.h.

{ return eMupIonization; }

---

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

• Generator/src/Physics/MuonEnergyLoss/BetheBlochModel.h
• Generator/src/Physics/MuonEnergyLoss/BetheBlochModel.cxx