[WIP] Ionization calculation based on MIP program (S. Biagi). More...

#include <TrackElectron.hh>

Inheritance diagram for Garfield::TrackElectron:

Classes
struct	Cluster

Public Member Functions
	TrackElectron ()
	Constructor.

virtual	~TrackElectron ()
	Destructor.

void	SetParticle (const std::string &particle) override

bool	NewTrack (const double x0, const double y0, const double z0, const double t0, const double dx0, const double dy0, const double dz0) override

bool	GetCluster (double &xc, double &yc, double &zc, double &tc, int &nc, double &ec, double &extra) override

const std::vector< Cluster > &	GetClusters () const

double	GetClusterDensity () override

double	GetStoppingPower () override
	Get the stopping power (mean energy loss [eV] per cm).

Public Member Functions inherited from Garfield::Track
	Track ()=delete
	Default constructor.

	Track (const std::string &name)
	Constructor.

virtual	~Track ()
	Destructor.

void	SetEnergy (const double e)
	Set the particle energy.

void	SetBetaGamma (const double bg)
	Set the relative momentum of the particle.

void	SetBeta (const double beta)
	Set the speed ( $\beta = v/c$ ) of the particle.

void	SetGamma (const double gamma)
	Set the Lorentz factor of the particle.

void	SetMomentum (const double p)
	Set the particle momentum.

void	SetKineticEnergy (const double ekin)
	Set the kinetic energy of the particle.

double	GetEnergy () const
	Return the particle energy.

double	GetBetaGamma () const
	Return the $\beta\gamma$ of the projectile.

double	GetBeta () const
	Return the speed ( $\beta = v/c$ ) of the projectile.

double	GetGamma () const
	Return the Lorentz factor of the projectile.

double	GetMomentum () const
	Return the particle momentum.

double	GetKineticEnergy () const
	Return the kinetic energy of the projectile.

double	GetCharge () const
	Get the charge of the projectile.

double	GetMass () const
	Get the mass [eV / c2] of the projectile.

void	SetSensor (Sensor *s)
	Set the sensor through which to transport the particle.

void	EnablePlotting (ViewDrift *viewer)
	Switch on plotting.

void	DisablePlotting ()
	Switch off plotting.

void	EnableDebugging ()
	Switch on debugging messages.

void	DisableDebugging ()
	Switch off debugging messages.

Additional Inherited Members
Protected Member Functions inherited from Garfield::Track
void	PlotNewTrack (const double x0, const double y0, const double z0)

void	PlotCluster (const double x0, const double y0, const double z0)

Static Protected Member Functions inherited from Garfield::Track
static std::array< double, 3 >	StepBfield (const double dt, const double qoverm, const double vmag, double bx, double by, double bz, std::array< double, 3 > &dir)

Protected Attributes inherited from Garfield::Track
std::string	m_className = "Track"

double	m_q = -1.

int	m_spin = 1

double	m_mass

double	m_energy = 0.

double	m_beta2 = 1.

bool	m_isElectron = false

std::string	m_particleName = "mu-"

Sensor *	m_sensor = nullptr

bool	m_isChanged = true

ViewDrift *	m_viewer = nullptr

bool	m_debug = false

size_t	m_plotId = 0

Detailed Description

[WIP] Ionization calculation based on MIP program (S. Biagi).

Definition at line 13 of file TrackElectron.hh.

Constructor & Destructor Documentation

◆ TrackElectron()

Garfield::TrackElectron::TrackElectron ( )

Constructor.

Definition at line 13 of file TrackElectron.cc.

                             : Track("Electron") {
 
  // Setup the particle properties.
  m_q = -1;
  m_spin = 1;
  m_mass = ElectronMass;
  m_isElectron = true;
  SetBetaGamma(3.);
  m_particleName = "electron";
}

◆ ~TrackElectron()

virtual Garfield::TrackElectron::~TrackElectron ( )

inlinevirtual

Destructor.

Definition at line 23 of file TrackElectron.hh.

23{}

Member Function Documentation

◆ GetCluster()

bool Garfield::TrackElectron::GetCluster	(	double &	xc,
		double &	yc,
		double &	zc,
		double &	tc,
		int &	nc,
		double &	ec,
		double &	extra )

overridevirtual

Get the next "cluster" (ionising collision of the charged particle).

Parameters

xc,yc,zc	coordinates of the collision
tc	time of the collision
nc	number of electrons produced
ec	deposited energy
extra	additional information (not always implemented)

Implements Garfield::Track.

Definition at line 124 of file TrackElectron.cc.

                                                                   {
  xc = yc = zc = tc = ec = extra = 0.;
  ne = 0;
  if (m_clusters.empty()) return false;
  // Increment the cluster index.
  if (m_cluster < m_clusters.size()) {
    ++m_cluster;
  } else if (m_cluster > m_clusters.size()) {
    m_cluster = 0;
  } 
  if (m_cluster >= m_clusters.size()) return false;
 
  xc = m_clusters[m_cluster].x;
  yc = m_clusters[m_cluster].y;
  zc = m_clusters[m_cluster].z;
  tc = m_clusters[m_cluster].t;
  ec = m_clusters[m_cluster].esec;
  ne = 1;
  return true;
}

◆ GetClusterDensity()

double Garfield::TrackElectron::GetClusterDensity ( )

overridevirtual

Get the cluster density (number of ionizing collisions per cm or inverse mean free path for ionization).

Reimplemented from Garfield::Track.

Definition at line 146 of file TrackElectron.cc.

                                        {
  return m_mfp > 0. ? 1. / m_mfp : 0.;
}

◆ GetClusters()

const std::vector< Cluster > & Garfield::TrackElectron::GetClusters ( ) const

inline

Definition at line 33 of file TrackElectron.hh.

33{ return m_clusters; }

◆ GetStoppingPower()

double Garfield::TrackElectron::GetStoppingPower ( )

overridevirtual

Get the stopping power (mean energy loss [eV] per cm).

Reimplemented from Garfield::Track.

Definition at line 150 of file TrackElectron.cc.

                                       {
  return m_dedx;
}

◆ NewTrack()

bool Garfield::TrackElectron::NewTrack	(	const double	x0,
		const double	y0,
		const double	z0,
		const double	t0,
		const double	dx0,
		const double	dy0,
		const double	dz0 )

overridevirtual

Calculate a new track starting from (x0, y0, z0) at time t0 in direction (dx0, dy0, dz0).

Implements Garfield::Track.

Definition at line 30 of file TrackElectron.cc.

                                                                 {
  // Reset the list of clusters.
  m_clusters.clear();
  m_cluster = 0;
  // Make sure the sensor has been set.
  if (!m_sensor) {
    std::cerr << m_className << "::NewTrack: Sensor is not defined.\n";
    return false;
  }
 
  // Make sure the medium at this location is an ionisable gas.
  Medium* medium = m_sensor->GetMedium(x0, y0, z0);
  if (!medium || !medium->IsIonisable() || !medium->IsGas()) {
    std::cerr << m_className << "::NewTrack:\n"
              << "    No ionisable gas medium at initial position.\n";
    return false;
  }
  std::vector<Parameters> par;
  std::vector<double> frac;
  if (!Setup(medium, par, frac)) {
    std::cerr << m_className << "::NewTrack:\n"
              << "    Properties of " << medium->GetName()
              << " are not implemented.\n";
    return false;
  }
 
  const std::string mediumName = medium->GetName();
  const double density = medium->GetNumberDensity();
 
  const size_t nComponents = frac.size();
  std::vector<double> prob(nComponents, 0.);
  double mfp = 0., dedx = 0.;
  if (!Update(density, m_beta2, par, frac, prob, mfp, dedx)) {
    std::cerr << m_className << "::NewTrack:\n"
              << "    Cross-sections could not be calculated.\n";
    return false;
  }
  m_mfp = mfp;
  m_dedx = dedx;
 
  double x = x0;
  double y = y0;
  double z = z0;
  double t = t0;
  double dx = dx0;
  double dy = dy0;
  double dz = dz0;
  const double d = sqrt(dx * dx + dy * dy + dz * dz);
  if (d < Small) {
    RndmDirection(dx, dy, dz);
  } else {
    // Normalize the direction vector.
    const double scale = 1. / d;
    dx *= scale;
    dy *= scale;
    dz *= scale;
  }
  const double dt = 1. / (sqrt(m_beta2) * SpeedOfLight);
  double e0 = ElectronMass * (sqrt(1. / (1. - m_beta2)) - 1.);
  while (e0 > 0.) {
    // Draw a step length and propagate the electron.
    const double step = -m_mfp * log(RndmUniformPos());
    x += step * dx;
    y += step * dy;
    z += step * dz;
    t += step * dt;
 
    medium = m_sensor->GetMedium(x, y, z);
    if (!medium || !medium->IsIonisable() ||
        medium->GetName() != mediumName ||
        medium->GetNumberDensity() != density) {
      break;
    }
    Cluster cluster;
    cluster.x = x;
    cluster.y = y;
    cluster.z = z;
    cluster.t = t;
    const double r = RndmUniform();
    for (size_t i = 0; i < nComponents; ++i) {
      if (r > prob[i]) continue;
      // Sample secondary electron energy according to
      // Opal-Beaty-Peterson splitting function.
      cluster.esec = Esec(e0, par[i]);
      m_clusters.push_back(std::move(cluster));
      break;
    }
  }
  m_cluster = m_clusters.size() + 2;
  return true;
}

◆ SetParticle()

void Garfield::TrackElectron::SetParticle ( const std::string & part )

overridevirtual

Set the type of charged particle.

electron,e-
positron,e+
muon,mu-
mu+
pion,pi-
pi+
kaon,K-
K+
proton,p
anti-proton,p-bar
deuteron,d
alpha

Reimplemented from Garfield::Track.

Definition at line 24 of file TrackElectron.cc.

                                                         {
  if (particle != "electron" && particle != "e" && particle != "e-") {
    std::cerr << m_className << "::SetParticle: Only electrons are allowed.\n";
  }
}

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

Classes

Public Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ TrackElectron()

◆ ~TrackElectron()

Member Function Documentation

◆ GetCluster()

◆ GetClusterDensity()

◆ GetClusters()

◆ GetStoppingPower()

◆ NewTrack()

◆ SetParticle()