DetectorConstruction.cc

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// $Id: DetectorConstruction.cc 77288 2013-11-22 10:52:58Z gcosmo $
//
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#include "DetectorConstruction.hh"
#include "DetectorMessenger.hh"

#include "G4NistManager.hh"
#include "G4Material.hh"
#include "G4Box.hh"
#include "G4LogicalVolume.hh"
#include "G4PVPlacement.hh"
#include "G4PVReplica.hh"
#include "G4UniformMagField.hh"

#include "G4GeometryManager.hh"
#include "G4PhysicalVolumeStore.hh"
#include "G4LogicalVolumeStore.hh"
#include "G4SolidStore.hh"

#include "G4UImanager.hh"
#include "G4UnitsTable.hh"
#include "G4PhysicalConstants.hh"
#include "G4SystemOfUnits.hh"
#include "G4GlobalMagFieldMessenger.hh"
#include "G4AutoDelete.hh"
#include "G4RunManager.hh"
#include <iomanip>

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DetectorConstruction::DetectorConstruction()
:G4VUserDetectorConstruction(),fDefaultMaterial(0),fPhysiWorld(0),
 fDetectorMessenger(0)
{
  // default parameter values of the absorbers
  fNbOfAbsor = 1;
  fAbsorThickness[0] = 0*mm;        //dummy, for initialization   
  fAbsorThickness[1] = 1*mm;  
  fAbsorSizeYZ       = 1*mm;

  ComputeParameters();

  // materials
  DefineMaterials();
  SetAbsorMaterial(1,"G4_Si");

  // create commands for interactive definition of the calorimeter
  fDetectorMessenger = new DetectorMessenger(this);
}

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DetectorConstruction::~DetectorConstruction()
{
  delete fDetectorMessenger;
}

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G4VPhysicalVolume* DetectorConstruction::Construct()
{
  return ConstructVolumes();
}

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void DetectorConstruction::DefineMaterials()
{
  G4NistManager* man = G4NistManager::Instance();

  man->FindOrBuildMaterial("G4_AIR");
  
  G4Element* H = man->FindOrBuildElement("H"); 
  G4Element* O = man->FindOrBuildElement("O");
  
  G4Material* H2O = 
  new G4Material("Water", 1.000*g/cm3, 2);
  H2O->AddElement(H, 2);
  H2O->AddElement(O, 1);
  H2O->GetIonisation()->SetMeanExcitationEnergy(78.0*eV);
  
  // example of vacuum
  G4double density     = universe_mean_density;    //from PhysicalConstants.h
  G4double pressure    = 3.e-18*pascal;
  G4double temperature = 2.73*kelvin;
  G4Material* Galactic =   
  new G4Material("Galactic", 1., 1.008*g/mole, density,
                             kStateGas,temperature,pressure);
                             
  fDefaultMaterial = Galactic;
  
  //  G4cout << *(G4Material::GetMaterialTable()) << G4endl;
}

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G4Material* DetectorConstruction::MaterialWithSingleIsotope( 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;
}

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void DetectorConstruction::ComputeParameters()
{
  // Compute total thickness of absorbers
  fAbsorSizeX = 0.;
  for (G4int iAbs=1; iAbs<=fNbOfAbsor; iAbs++) {
    fAbsorSizeX += fAbsorThickness[iAbs];
  }
  fWorldSizeX  = 1.2*fAbsorSizeX;
  fWorldSizeYZ = 1.2*fAbsorSizeYZ;
}

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G4VPhysicalVolume* DetectorConstruction::ConstructVolumes()
{
  // complete the Calor parameters definition
  ComputeParameters();

  // Cleanup old geometry
  G4GeometryManager::GetInstance()->OpenGeometry();
  G4PhysicalVolumeStore::GetInstance()->Clean();
  G4LogicalVolumeStore::GetInstance()->Clean();
  G4SolidStore::GetInstance()->Clean();

  //
  // World
  //
  G4Box* solidWorld =
    new G4Box("World",                                             //name
               fWorldSizeX/2,fWorldSizeYZ/2,fWorldSizeYZ/2);       //size

  G4LogicalVolume* logicWorld =
    new G4LogicalVolume(solidWorld,              //solid
                        fDefaultMaterial,        //material
                        "World");                //name

  fPhysiWorld = 
    new G4PVPlacement(0,                        //no rotation
                        G4ThreeVector(),        //at (0,0,0)
                      logicWorld,               //logical volume
                      "World",                  //name
                       0,                       //mother volume
                       false,                   //no boolean operation
                       0);                      //copy number
                                 
  //
  // Absorbers
  //
  fXfront[0] = -0.5*fAbsorSizeX;
  //
  for (G4int k=1; k<=fNbOfAbsor; k++) {
    G4Material* material = fAbsorMaterial[k];
    G4String matname = material->GetName();
      
    G4Box* solidAbsor =
      new G4Box(matname,fAbsorThickness[k]/2,fAbsorSizeYZ/2,fAbsorSizeYZ/2);

    G4LogicalVolume* logicAbsor =
      new G4LogicalVolume(solidAbsor,           // solid
                          material,             // material
                          matname);             // name
                                     
    fXfront[k] = fXfront[k-1] + fAbsorThickness[k-1];    
    G4double xcenter = fXfront[k]+0.5*fAbsorThickness[k];
    G4ThreeVector position = G4ThreeVector(xcenter,0.,0.);
  
      new G4PVPlacement(0,                     //no rotation
                              position,        //position
                        logicAbsor,            //logical volume        
                        matname,               //name
                        logicWorld,            //mother
                        false,                 //no boulean operat
                        k);                    //copy number
  }

  PrintParameters();

  //always return the physical World
  //
  return fPhysiWorld;
}

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void DetectorConstruction::PrintParameters()
{
  G4cout << "\n-------------------------------------------------------------"
         << "\n ---> The Absorber is " << fNbOfAbsor << " layers of:";
  for (G4int i=1; i<=fNbOfAbsor; i++)
     {
      G4cout << "\n \t" << std::setw(12) << fAbsorMaterial[i]->GetName() <<": "
              << std::setw(6) << G4BestUnit(fAbsorThickness[i],"Length");
     }
  G4cout << "\n-------------------------------------------------------------\n"
         << G4endl;
}

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void DetectorConstruction::SetNbOfAbsor(G4int ival)
{
  // set the number of Absorbers
  //
  if (ival < 1 || ival > (kMaxAbsor-1))
    { G4cout << "\n ---> warning from SetfNbOfAbsor: "
             << ival << " must be at least 1 and and most " << kMaxAbsor-1
             << ". Command refused" << G4endl;
      return;
    }
  fNbOfAbsor = ival;
  G4RunManager::GetRunManager()->ReinitializeGeometry();
}

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void DetectorConstruction::SetAbsorMaterial(G4int iabs,const G4String& material)
{
  // search the material by its name
  //
  if (iabs > fNbOfAbsor || iabs <= 0)
    { G4cout << "\n --->warning from SetfAbsorMaterial: absor number "
             << iabs << " out of range. Command refused" << G4endl;
      return;
    }

  G4Material* pttoMaterial = 
    G4NistManager::Instance()->FindOrBuildMaterial(material);
  if (pttoMaterial) {
      fAbsorMaterial[iabs] = pttoMaterial;
      G4RunManager::GetRunManager()->PhysicsHasBeenModified();
  }
}

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void DetectorConstruction::SetAbsorThickness(G4int iabs,G4double val)
{
  // change Absorber thickness
  //
  if (iabs > fNbOfAbsor || iabs <= 0)
    { G4cout << "\n --->warning from SetfAbsorThickness: absor number "
             << iabs << " out of range. Command refused" << G4endl;
      return;
    }
  if (val <= DBL_MIN)
    { G4cout << "\n --->warning from SetfAbsorThickness: thickness "
             << val  << " out of range. Command refused" << G4endl;
      return;
    }
  fAbsorThickness[iabs] = val;
  G4RunManager::GetRunManager()->ReinitializeGeometry();
}

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void DetectorConstruction::SetAbsorSizeYZ(G4double val)
{
  // change the transverse size
  //
  if (val <= DBL_MIN)
    { G4cout << "\n --->warning from SetfAbsorSizeYZ: thickness "
             << val  << " out of range. Command refused" << G4endl;
      return;
    }
  fAbsorSizeYZ = val;
  G4RunManager::GetRunManager()->ReinitializeGeometry();
}

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void DetectorConstruction::ConstructSDandField()
{
    if ( fFieldMessenger.Get() == 0 ) {
        // Create global magnetic field messenger.
        // Uniform magnetic field is then created automatically if
        // the field value is not zero.
        G4ThreeVector fieldValue = G4ThreeVector();
        G4GlobalMagFieldMessenger* msg =
        new G4GlobalMagFieldMessenger(fieldValue);
        //msg->SetVerboseLevel(1);
        G4AutoDelete::Register(msg);
        fFieldMessenger.Put( msg );
    }
}

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