G4VPhysicalVolume * GeantDetectorConstruction::Construct() { // World G4double worldSize = 5 * ( std::abs( gOptions->GetDetZ_cm() * cm ) + std::abs( gOptions->GetPartZ_cm() * cm ) ) ; G4Box * worldSolid = new G4Box("WorldS", worldSize, worldSize, worldSize); G4LogicalVolume * worldLV = new G4LogicalVolume( worldSolid, G4NistManager::Instance()->FindOrBuildMaterial("G4_Galactic"), "World"); G4VPhysicalVolume * worldPV = new G4PVPlacement( 0, G4ThreeVector(0,0,0), worldLV, "WorldPV", 0, false, 0, true); // Scatterer plane G4Box * scatPlaneSolid = new G4Box("scatPlaneSolid", worldSize, worldSize, gOptions->GetScatThick_um() * um / 2 ); G4Material * scatMat = G4NistManager::Instance()->FindOrBuildMaterial("G4_Si"); G4cout << "Scatterer material: " << scatMat->GetName() << " Radiation length = "<< scatMat->GetRadlen() / cm << " cm"<< G4endl; G4LogicalVolume * scatPlaneLV = new G4LogicalVolume( scatPlaneSolid, scatMat, "scatPlaneLV"); new G4PVPlacement( 0, G4ThreeVector(0,0,0), scatPlaneLV, "scatPlanePV", worldLV, false, 0, true); // Detector plane G4Box * detPlaneSolid = new G4Box("detPlaneSolid", worldSize, worldSize, 1 * um ); G4LogicalVolume * detPlaneLV = new G4LogicalVolume( detPlaneSolid, G4NistManager::Instance()->FindOrBuildMaterial("G4_Galactic"), "detPlaneLV"); new G4PVPlacement( 0, G4ThreeVector( 0, 0, ( gOptions->GetDetZ_cm() + detPlaneSolid->GetZHalfLength() ) * cm ), detPlaneLV, "DetPlanePV", worldLV, false, 0, true); fDetPlaneSD = new GeantTrackerSD( 0 ); SetSensitiveDetector( detPlaneLV, fDetPlaneSD ); return worldPV; }