B4::DetectorConstruction Class Reference

Detector construction class to define materials and geometry. More...

#include <Doxymodules_basic.h>

Inheritance diagram for B4::DetectorConstruction:

Public Member Functions
	DetectorConstruction ()=default
	~DetectorConstruction () override=default
G4VPhysicalVolume *	Construct () override
void	ConstructSDandField () override
const G4VPhysicalVolume *	GetAbsorberPV () const
const G4VPhysicalVolume *	GetGapPV () const

Private Member Functions
void	DefineMaterials ()
G4VPhysicalVolume *	DefineVolumes ()

Private Attributes
G4VPhysicalVolume *	fAbsorberPV = nullptr
G4VPhysicalVolume *	fGapPV = nullptr
G4bool	fCheckOverlaps = true

Static Private Attributes
static G4ThreadLocal G4GlobalMagFieldMessenger *	fMagFieldMessenger = nullptr

Detailed Description

Detector construction class to define materials and geometry.

The calorimeter is a box made of a given number of layers. A layer consists of an absorber plate and of a detection gap. The layer is replicated.

Four parameters define the geometry of the calorimeter :

• the thickness of an absorber plate,
• the thickness of a gap,
• the number of layers,
• the transverse size of the calorimeter (the input face is a square).

In addition a transverse uniform magnetic field is defined via G4GlobalMagFieldMessenger class.

Definition at line 123 of file Doxymodules_basic.h.

Constructor & Destructor Documentation

DetectorConstruction()

B4::DetectorConstruction::DetectorConstruction ( )

default

~DetectorConstruction()

B4::DetectorConstruction::~DetectorConstruction ( )

overridedefault

Member Function Documentation

Construct()

G4VPhysicalVolume * B4::DetectorConstruction::Construct ( )

override

Definition at line 63 of file DetectorConstruction.cc.

{
  // Define materials
  DefineMaterials();
 
  // Define volumes
  return DefineVolumes();
}

ConstructSDandField()

void B4::DetectorConstruction::ConstructSDandField ( )

override

Definition at line 257 of file DetectorConstruction.cc.

{
  // Create global magnetic field messenger.
  // Uniform magnetic field is then created automatically if
  // the field value is not zero.
  G4ThreeVector fieldValue;
  fMagFieldMessenger = new G4GlobalMagFieldMessenger(fieldValue);
  fMagFieldMessenger->SetVerboseLevel(1);
 
  // Register the field messenger for deleting
  G4AutoDelete::Register(fMagFieldMessenger);
}

GetAbsorberPV()

const G4VPhysicalVolume * B4::DetectorConstruction::GetAbsorberPV ( ) const

inline

Definition at line 90 of file DetectorConstruction.hh.

                                                                          {
  return fAbsorberPV;
}

GetGapPV()

const G4VPhysicalVolume * B4::DetectorConstruction::GetGapPV ( ) const

inline

Definition at line 94 of file DetectorConstruction.hh.

                                                                      {
  return fGapPV;
}

DefineMaterials()

void B4::DetectorConstruction::DefineMaterials ( )

private

Definition at line 74 of file DetectorConstruction.cc.

{
  // Lead material defined using NIST Manager
  auto nistManager = G4NistManager::Instance();
  nistManager->FindOrBuildMaterial("G4_Pb");
 
  // Liquid argon material
  G4double a;  // mass of a mole;
  G4double z;  // z=mean number of protons;
  G4double density;
  new G4Material("liquidArgon", z=18., a= 39.95*g/mole, density= 1.390*g/cm3);
         // The argon by NIST Manager is a gas with a different density
 
  // Vacuum
  new G4Material("Galactic", z=1., a=1.01*g/mole,density= universe_mean_density,
                  kStateGas, 2.73*kelvin, 3.e-18*pascal);
 
  // Print materials
  G4cout << *(G4Material::GetMaterialTable()) << G4endl;
}

DefineVolumes()

G4VPhysicalVolume * B4::DetectorConstruction::DefineVolumes ( )

private

Definition at line 97 of file DetectorConstruction.cc.

{
  // Geometry parameters
  G4int nofLayers = 10;
  G4double absoThickness = 10.*mm;
  G4double gapThickness =  5.*mm;
  G4double calorSizeXY  = 10.*cm;
 
  auto layerThickness = absoThickness + gapThickness;
  auto calorThickness = nofLayers * layerThickness;
  auto worldSizeXY = 1.2 * calorSizeXY;
  auto worldSizeZ  = 1.2 * calorThickness;
 
  // Get materials
  auto defaultMaterial = G4Material::GetMaterial("Galactic");
  auto absorberMaterial = G4Material::GetMaterial("G4_Pb");
  auto gapMaterial = G4Material::GetMaterial("liquidArgon");
 
  if ( ! defaultMaterial || ! absorberMaterial || ! gapMaterial ) {
    G4ExceptionDescription msg;
    msg << "Cannot retrieve materials already defined.";
    G4Exception("DetectorConstruction::DefineVolumes()",
      "MyCode0001", FatalException, msg);
  }
 
  //
  // World
  //
  auto worldS
    = new G4Box("World",           // its name
                 worldSizeXY/2, worldSizeXY/2, worldSizeZ/2); // its size
 
  auto worldLV
    = new G4LogicalVolume(
                 worldS,           // its solid
                 defaultMaterial,  // its material
                 "World");         // its name
 
  auto worldPV = new G4PVPlacement(nullptr,  // no rotation
    G4ThreeVector(),                         // at (0,0,0)
    worldLV,                                 // its logical volume
    "World",                                 // its name
    nullptr,                                 // its mother  volume
    false,                                   // no boolean operation
    0,                                       // copy number
    fCheckOverlaps);                         // checking overlaps
 
  //
  // Calorimeter
  //
  auto calorimeterS
    = new G4Box("Calorimeter",     // its name
                 calorSizeXY/2, calorSizeXY/2, calorThickness/2); // its size
 
  auto calorLV
    = new G4LogicalVolume(
                 calorimeterS,     // its solid
                 defaultMaterial,  // its material
                 "Calorimeter");   // its name
 
  new G4PVPlacement(nullptr,  // no rotation
    G4ThreeVector(),          // at (0,0,0)
    calorLV,                  // its logical volume
    "Calorimeter",            // its name
    worldLV,                  // its mother  volume
    false,                    // no boolean operation
    0,                        // copy number
    fCheckOverlaps);          // checking overlaps
 
  //
  // Layer
  //
  auto layerS
    = new G4Box("Layer",           // its name
                 calorSizeXY/2, calorSizeXY/2, layerThickness/2); // its size
 
  auto layerLV
    = new G4LogicalVolume(
                 layerS,           // its solid
                 defaultMaterial,  // its material
                 "Layer");         // its name
 
  new G4PVReplica(
                 "Layer",          // its name
                 layerLV,          // its logical volume
                 calorLV,          // its mother
                 kZAxis,           // axis of replication
                 nofLayers,        // number of replica
                 layerThickness);  // witdth of replica
 
  //
  // Absorber
  //
  auto absorberS
    = new G4Box("Abso",            // its name
                 calorSizeXY/2, calorSizeXY/2, absoThickness/2); // its size
 
  auto absorberLV
    = new G4LogicalVolume(
                 absorberS,        // its solid
                 absorberMaterial, // its material
                 "Abso");          // its name
 
  fAbsorberPV = new G4PVPlacement(nullptr,     // no rotation
    G4ThreeVector(0., 0., -gapThickness / 2),  // its position
    absorberLV,                                // its logical volume
    "Abso",                                    // its name
    layerLV,                                   // its mother  volume
    false,                                     // no boolean operation
    0,                                         // copy number
    fCheckOverlaps);                           // checking overlaps
 
  //
  // Gap
  //
  auto gapS
    = new G4Box("Gap",             // its name
                 calorSizeXY/2, calorSizeXY/2, gapThickness/2); // its size
 
  auto gapLV
    = new G4LogicalVolume(
                 gapS,             // its solid
                 gapMaterial,      // its material
                 "Gap");           // its name
 
  fGapPV = new G4PVPlacement(nullptr,          // no rotation
    G4ThreeVector(0., 0., absoThickness / 2),  // its position
    gapLV,                                     // its logical volume
    "Gap",                                     // its name
    layerLV,                                   // its mother  volume
    false,                                     // no boolean operation
    0,                                         // copy number
    fCheckOverlaps);                           // checking overlaps
 
  //
  // print parameters
  //
  G4cout
    << G4endl
    << "------------------------------------------------------------" << G4endl
    << "---> The calorimeter is " << nofLayers << " layers of: [ "
    << absoThickness/mm << "mm of " << absorberMaterial->GetName()
    << " + "
    << gapThickness/mm << "mm of " << gapMaterial->GetName() << " ] " << G4endl
    << "------------------------------------------------------------" << G4endl;
 
  //
  // Visualization attributes
  //
  worldLV->SetVisAttributes(G4VisAttributes::GetInvisible());
  calorLV->SetVisAttributes(G4VisAttributes(G4Colour::White()));
 
  //
  // Always return the physical World
  //
  return worldPV;
}

Member Data Documentation

fMagFieldMessenger

G4ThreadLocal G4GlobalMagFieldMessenger * B4::DetectorConstruction::fMagFieldMessenger = nullptr

staticprivate

Definition at line 79 of file DetectorConstruction.hh.

fAbsorberPV

G4VPhysicalVolume* B4::DetectorConstruction::fAbsorberPV = nullptr

private

Definition at line 82 of file DetectorConstruction.hh.

fGapPV

G4VPhysicalVolume* B4::DetectorConstruction::fGapPV = nullptr

private

Definition at line 83 of file DetectorConstruction.hh.

fCheckOverlaps

G4bool B4::DetectorConstruction::fCheckOverlaps = true

private

Definition at line 85 of file DetectorConstruction.hh.

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

• .doxygen/Doxymodules_basic.h
• basic/B4/B4a/include/DetectorConstruction.hh
• basic/B4/B4a/src/DetectorConstruction.cc