GarfieldDetectorConstruction.cc

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// $Id: GarfieldDetectorConstruction.cc 999992 2015-12-11 14:47:43Z dpfeiffe $
//
/// \file GarfieldDetectorConstruction.cc
/// \brief Implementation of the GarfieldDetectorConstruction class
 
#include "GarfieldDetectorConstruction.hh"
 
#include "G4AutoDelete.hh"
#include "G4Box.hh"
#include "G4Colour.hh"
#include "G4GeometryManager.hh"
#include "G4GlobalMagFieldMessenger.hh"
#include "G4LogicalVolume.hh"
#include "G4LogicalVolumeStore.hh"
#include "G4Material.hh"
#include "G4NistManager.hh"
#include "G4PVPlacement.hh"
#include "G4PVReplica.hh"
#include "G4PhysicalConstants.hh"
#include "G4PhysicalVolumeStore.hh"
#include "G4RunManager.hh"
#include "G4SolidStore.hh"
#include "G4SystemOfUnits.hh"
#include "G4Tubs.hh"
#include "G4VisAttributes.hh"
#include "GarfieldG4FastSimulationModel.hh"
#include "GarfieldMessenger.hh"
 
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GarfieldDetectorConstruction::GarfieldDetectorConstruction()
    : G4VUserDetectorConstruction() {
  fGarfieldMessenger = new GarfieldMessenger(this);
}
 
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GarfieldDetectorConstruction::~GarfieldDetectorConstruction() {
  delete fGarfieldMessenger;
}
 
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G4VPhysicalVolume* GarfieldDetectorConstruction::Construct() {
  // Define materials
  DefineMaterials();
 
  // Define volumes
  return DefineVolumes();
}
 
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
 
void GarfieldDetectorConstruction::DefineMaterials() {
  G4bool isotopes = false;
  G4String name, symbol;
  G4int ncomponents, natoms;
  G4double density, fractionmass;
 
  // Lead material defined using NIST Manager
  G4NistManager* nistManager = G4NistManager::Instance();
 
  nistManager->FindOrBuildMaterial("G4_Pb");
  nistManager->FindOrBuildMaterial("G4_Cu");
  nistManager->FindOrBuildMaterial("G4_Al");
  nistManager->FindOrBuildMaterial("G4_Au");
  nistManager->FindOrBuildMaterial("G4_W");
 
  nistManager->FindOrBuildMaterial("G4_AIR");
 
  G4Element* H = nistManager->FindOrBuildElement("H", isotopes);
  G4Element* N = nistManager->FindOrBuildElement("N", isotopes);
  G4Element* C = nistManager->FindOrBuildElement("C", isotopes);
  G4Element* O = nistManager->FindOrBuildElement("O", isotopes);
  G4Element* Ar = nistManager->FindOrBuildElement("Ar", isotopes);
 
  G4Material* CO2 = new G4Material(
      "CO2", density = 1.977 * CLHEP::mg / CLHEP::cm3, ncomponents = 2);
  CO2->AddElement(C, natoms = 1);
  CO2->AddElement(O, natoms = 2);
 
  G4Material* ArCO2_70_30 =
      new G4Material("ArCO2_70_30", density = 1.8223 * CLHEP::mg / CLHEP::cm3,
                     ncomponents = 2, kStateGas);
  ArCO2_70_30->AddElement(Ar, fractionmass = 0.70);
  ArCO2_70_30->AddMaterial(CO2, fractionmass = 0.30);
 
  density = 1.413 * CLHEP::g / CLHEP::cm3;
  G4Material* Kapton =
      new G4Material(name = "Kapton", density, ncomponents = 4);
  Kapton->AddElement(O, 5);
  Kapton->AddElement(C, 22);
  Kapton->AddElement(N, 2);
  Kapton->AddElement(H, 10);
 
  // Print materials
  G4cout << *(G4Material::GetMaterialTable()) << G4endl;
}
 
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
 
G4VPhysicalVolume* GarfieldDetectorConstruction::DefineVolumes() {
  // Geometry parameters
  G4double worldSizeXYZ = 1000 * mm;
  G4double absorberThicknessZ = 10. * mm;
  G4double absorberThicknessXY = 100. * mm;
  G4double wireRadius = 0.025 * mm;
  G4double tubeRadius = 15 * mm;
  G4double tubeHalfLength = 100 * mm;
  G4double tubeThickness = 500 * um;
 
  // Get materials
  G4Material* defaultMaterial = G4Material::GetMaterial("G4_AIR");
  fAbsorberMaterial = G4Material::GetMaterial("G4_Pb");
 
  G4Material* gasMaterial = G4Material::GetMaterial("ArCO2_70_30");
  G4Material* cathodeMaterial = G4Material::GetMaterial("G4_Al");
  G4Material* wireMaterial = G4Material::GetMaterial("G4_W");
 
  if (!defaultMaterial || !fAbsorberMaterial || !gasMaterial ||
      !cathodeMaterial || !wireMaterial) {
    G4ExceptionDescription msg;
    msg << "Cannot retrieve materials already defined.";
    G4Exception("GarfieldDetectorConstruction::DefineVolumes()",
                "exampleGarfield", FatalException, msg);
  }
 
  //
  // World
  //
  G4VSolid* worldS = new G4Box("World",  // its name
                               0.5 * worldSizeXYZ, 0.5 * worldSizeXYZ,
                               0.5 * worldSizeXYZ);  // its size
 
  G4LogicalVolume* worldLV =
      new G4LogicalVolume(worldS,           // its solid
                          defaultMaterial,  // its material
                          "World");         // its name
 
  G4VPhysicalVolume* worldPV =
      new G4PVPlacement(0,                // no rotation
                        G4ThreeVector(),  // at (0,0,0)
                        worldLV,          // its logical volume
                        "World",          // its name
                        0,                // its mother  volume
                        false,            // no boolean operation
                        0,                // copy number
                        fCheckOverlaps);  // checking overlaps
  //
  // Absorber
  //
  G4VSolid* absorberS =
      new G4Box("Absorber",  // its name
                0.5 * absorberThicknessXY, 0.5 * absorberThicknessXY,
                0.5 * absorberThicknessZ);  // its size
 
  fAbsorberLV = new G4LogicalVolume(absorberS,          // its solid
                                    fAbsorberMaterial,  // its material
                                    "Absorber");        // its name
 
  fAbsorberPV = new G4PVPlacement(
      0,                                              // no rotation
      G4ThreeVector(0., 0., absorberThicknessZ / 2),  // its position
      fAbsorberLV,                                    // its logical volume
      "Absorber",                                     // its name
      worldLV,                                        // its mother  volume
      false,                                          // no boolean operation
      0,                                              // copy number
      fCheckOverlaps);                                // checking overlaps
 
  //
  // Drift tube
  //
  G4VSolid* tubeS = new G4Tubs("Tube",  // its name
                               0, tubeRadius, tubeHalfLength + tubeThickness, 0,
                               2 * pi);  // its size
 
  G4LogicalVolume* tubeLV =
      new G4LogicalVolume(tubeS,            // its solid
                          cathodeMaterial,  // its material
                          "Tube");          // its name
 
  G4RotationMatrix* rotY = new G4RotationMatrix();
  rotY->rotateY(90. * CLHEP::degree);
 
  fTubePV = new G4PVPlacement(
      rotY,
      G4ThreeVector(0., -0.2 * tubeRadius,
                    absorberThicknessZ + tubeRadius),  // its position
      tubeLV,                                          // its logical volume
      "Tube",                                          // its name
      worldLV,                                         // its mother  volume
      false,                                           // no boolean operation
      0,                                               // copy number
      fCheckOverlaps);                                 // checking overlaps
 
  //
  // Drift Tube Gas
  //
  G4VSolid* gasS = new G4Tubs("Gas",  // its name
                              wireRadius, tubeRadius - tubeThickness,
                              tubeHalfLength, 0, 2 * pi);  // its size
 
  G4LogicalVolume* gasLV = new G4LogicalVolume(gasS,         // its solid
                                               gasMaterial,  // its material
                                               "Gas");       // its name
 
  fGasPV = new G4PVPlacement(0,                          // no rotation
                             G4ThreeVector(0., 0., 0.),  // its position
                             gasLV,                      // its logical volume
                             "Gas",                      // its name
                             tubeLV,                     // its mother  volume
                             false,                      // no boolean operation
                             0,                          // copy number
                             fCheckOverlaps);            // checking overlaps
 
  //
  // Wire
  //
  G4VSolid* wireS =
      new G4Tubs("Wire",                                     // its name
                 0, wireRadius, tubeHalfLength, 0, 2 * pi);  // its size
 
  G4LogicalVolume* wireLV = new G4LogicalVolume(wireS,         // its solid
                                                wireMaterial,  // its material
                                                "Wire");       // its name
 
  fWirePV = new G4PVPlacement(0,                          // no rotation
                              G4ThreeVector(0., 0., 0.),  // its position
                              wireLV,                     // its logical volume
                              "Wire",                     // its name
                              tubeLV,                     // its mother  volume
                              false,            // no boolean operation
                              0,                // copy number
                              fCheckOverlaps);  // checking overlaps
 
  //
  // Visualization attributes
  //
  worldLV->SetVisAttributes(G4VisAttributes::Invisible);
 
  G4VisAttributes* VisAttBlue = new G4VisAttributes(G4Colour(0.0, 0.0, 1.0));
  G4VisAttributes* VisAttGreen = new G4VisAttributes(G4Colour(0.0, 1.0, 0.0));
  G4VisAttributes* VisAttRed = new G4VisAttributes(G4Colour(1.0, 0.0, 0.0));
  G4VisAttributes* VisAttWhite = new G4VisAttributes(G4Colour(1.0, 1.0, 1.0));
 
  wireLV->SetVisAttributes(VisAttRed);
  tubeLV->SetVisAttributes(VisAttGreen);
  gasLV->SetVisAttributes(VisAttWhite);
  fAbsorberLV->SetVisAttributes(VisAttBlue);
 
  G4Region* regionGarfield = new G4Region("RegionGarfield");
  regionGarfield->AddRootLogicalVolume(gasLV);
 
  G4Region* regionWire = new G4Region("RegionWire");
  regionWire->AddRootLogicalVolume(wireLV);
 
  fGarfieldG4FastSimulationModel = new GarfieldG4FastSimulationModel(
      "GarfieldG4FastSimulationModel", regionGarfield);
 
  fGarfieldG4FastSimulationModel->WriteGeometryToGDML(fGasPV);
 
  //
  // Always return the physical World
  //
  return worldPV;
}
 
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
 
G4Material* GarfieldDetectorConstruction::AbsorberMaterialWithSingleIsotope(
    G4String name, G4String symbol, G4double density, G4int Z, G4int A) {
  // define a material from an isotope
  //
  G4int ncomponents;
  G4double abundance, massfraction;
 
  G4Isotope* isotope = new G4Isotope(symbol, Z, A);
 
  G4Element* element = new G4Element(name, symbol, ncomponents = 1);
  element->AddIsotope(isotope, abundance = 100. * perCent);
 
  G4Material* material = new G4Material(name, density, ncomponents = 1);
  material->AddElement(element, massfraction = 100. * perCent);
 
  return material;
}
 
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......
 
void GarfieldDetectorConstruction::SetAbsorberMaterial(
    G4String materialChoice) {
  // search the material by its name
  G4Material* newMaterial =
      G4NistManager::Instance()->FindOrBuildMaterial(materialChoice);
 
  if (newMaterial) {
    if (fAbsorberMaterial != newMaterial) {
      fAbsorberMaterial = newMaterial;
      if (fAbsorberLV) {
        fAbsorberLV->SetMaterial(fAbsorberMaterial);
      }
      G4RunManager::GetRunManager()->PhysicsHasBeenModified();
    }
  } else {
    G4cout << "\n--> warning from GarfieldDetectorConstruction::SetMaterial : "
           << materialChoice << " not found" << G4endl;
  }
}
 
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo......