UltraDetectorConstruction.cc

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//
//
// --------------------------------------------------------------
//                 GEANT 4 - ULTRA experiment example
// --------------------------------------------------------------
//
// Code developed by:
// B. Tome, M.C. Espirito-Santo, A. Trindade, P. Rodrigues 
//
//    ****************************************************
//    *      UltraDetectorConstruction.cc
//    ****************************************************
//
//    Class used in the definition of the Ultra setup consisting of:
//      - the UVscope detector
//      - an optional reflecting surface
//    Optical photons can reach the UVscope either directly or after reflection in the
//    surface, which can be polished or diffusing.
//    The main part of the UVscope definition is the Fresnel lens construction based
//    on the UltraFresnelLens class.
//
#include <cmath>

#include "UltraDetectorConstruction.hh"
#include "UltraPMTSD.hh"
#include "UltraFresnelLens.hh"

#include "G4PhysicalConstants.hh"
#include "G4SystemOfUnits.hh"
#include "G4Material.hh"
#include "G4MaterialTable.hh"
#include "G4Element.hh"
#include "G4ElementTable.hh"
#include "G4LogicalBorderSurface.hh"
#include "G4Box.hh"
#include "G4Sphere.hh"
#include "G4Tubs.hh"
#include "G4LogicalVolume.hh"
#include "G4RotationMatrix.hh"
#include "G4ThreeVector.hh"
#include "G4Transform3D.hh"
#include "G4PVPlacement.hh"
#include "G4OpBoundaryProcess.hh"
#include "G4VisAttributes.hh"
#include "G4Colour.hh"

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

UltraDetectorConstruction::UltraDetectorConstruction() : 
  logicalPMT(0)
{
  // Define wavelength limits for materials definition
  lambda_min = 200*nm ; 
  lambda_max = 700*nm ;   
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

UltraDetectorConstruction::~UltraDetectorConstruction(){;}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

G4VPhysicalVolume* UltraDetectorConstruction::Construct()
{
  ConstructTableMaterials();



//  The experimental Hall
//  ---------------------

  G4double World_x = 1.*m;
  G4double World_y = 1.*m;
  G4double World_z = 2*m;

  G4Box * World_box = new G4Box("World",World_x,World_y,World_z);

  // Get Air pointer from static funcion - (G4Material::GetMaterial)

G4String name;
G4Material *Air = G4Material::GetMaterial(name = "Air");
G4LogicalVolume *World_log ;
World_log  = new G4LogicalVolume(World_box,Air,"World",0,0,0);

G4VPhysicalVolume *World_phys ;
World_phys   = new G4PVPlacement(0,G4ThreeVector(),"World",World_log,0,false,0);

   G4VisAttributes* UniverseVisAtt = new G4VisAttributes(G4Colour(1.0,1.0,1.0));
   UniverseVisAtt->SetVisibility(true);
   UniverseVisAtt->SetForceWireframe(true);
   World_log->SetVisAttributes(UniverseVisAtt);
   World_log->SetVisAttributes (G4VisAttributes::Invisible);



  G4cout << "\n \n \n \n \n \n \n \n \n \n \n \n \n " << G4endl ;

  G4cout << "######################################################" << G4endl ;
  G4cout << "#                                                    #" << G4endl ;
  G4cout << "#                                                    #" << G4endl ;
  G4cout << "#          UltraDetectorConstruction:                #" << G4endl ;
  G4cout << "#                                                    #" << G4endl ;  
  G4cout << "#                                                    #" << G4endl ;  

  ConstructUVscope(World_phys);


  G4cout << "#                                                    #" << G4endl ;
  G4cout << "#                                                    #" << G4endl ;
  G4cout << "######################################################" << G4endl ;


#ifdef ULTRA_MIRROR_USE

  G4cout << "Using mirror reflecting surface " << G4endl ;

  G4VPhysicalVolume* Mirror ;
  Mirror = ConstructMirror(World_phys);

#elif ULTRA_GROUND_USE

  G4cout << "Using ground reflecting surface " << G4endl ;

  G4VPhysicalVolume* Ground ;
  Ground = ConstructGround(World_phys);

#else

  G4cout << "No reflecting surface used" << G4endl ;

#endif

  return World_phys;
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

void UltraDetectorConstruction::ConstructSDandField()
{ 
  UltraPMTSD* PMTSD = new UltraPMTSD("PMTSD");
  SetSensitiveDetector(logicalPMT,PMTSD);  
}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

void UltraDetectorConstruction::ConstructTableMaterials()
{
  G4double a, z, density;
  G4String name, symbol;
  G4int nel;


//  ------------- Elements -------------
  a = 1.01*g/mole;
  G4Element* elH  = new G4Element(name="Hydrogen", symbol="H", z=1., a);

  a = 12.01*g/mole;
  G4Element* elC  = new G4Element(name="Carbon",   symbol="C", z=6., a);

  a = 14.01*g/mole;
  G4Element* elN  = new G4Element(name="Nitrogen", symbol="N", z=7., a);

  a = 16.00*g/mole;
  G4Element* elO  = new G4Element(name="Oxygen",   symbol="O", z=8., a);

  a = 28.09*g/mole;
  G4Element* elSi = new G4Element(name="Silicon", symbol="Si", z=14., a);


//  ------------- Materials -------------


// Air
// ---
  density = 1.29e-03*g/cm3;
  G4Material* Air = new G4Material(name="Air", density, nel=2);
  Air->AddElement(elN, .7);
  Air->AddElement(elO, .3);


// Aluminum 
// ---------
  a = 26.98*g/mole;
  density = 2.7*g/cm3;
  new G4Material(name="Aluminum", z=13., a, density); 


// Quartz
// -------
//  density = 2.200*g/cm3; // fused quartz 
  density = 2.64*g/cm3;  // crystalline quartz (c.f. PDG) 
  G4Material *Quartz = new G4Material(name="Quartz",density, nel=2);
  Quartz->AddElement(elSi, 1) ;
  Quartz->AddElement(elO , 2) ;


// PMMA C5H8O2 ( Acrylic )
// -------------
   density = 1.19*g/cm3;
   G4Material* Acrylic = new G4Material(name="Acrylic", density, nel=3);
   Acrylic->AddElement(elC, 5);
   Acrylic->AddElement(elH, 8);
   Acrylic->AddElement(elO, 2);


/////////////////////////////////////////////
// Construct Material Properties Tables
/////////////////////////////////////////////

  const G4int NUMENTRIES = 2;

  // Energy bins
  G4double X_RINDEX[NUMENTRIES] = {h_Planck*c_light/lambda_max, h_Planck*c_light/lambda_min} ; 


  // Air
  G4double RINDEX_AIR[NUMENTRIES] = {1.00, 1.00} ; 

// Air refractive index at 20 oC and 1 atm (from PDG) 
  for(G4int j=0 ; j<NUMENTRIES ; j++){
    RINDEX_AIR[j] = RINDEX_AIR[j] + 2.73*std::pow(10.0,-4) ; 
    }

  G4MaterialPropertiesTable *MPT_Air = new G4MaterialPropertiesTable();
  MPT_Air->AddProperty("RINDEX", X_RINDEX, RINDEX_AIR, NUMENTRIES);
  Air->SetMaterialPropertiesTable(MPT_Air);

//////////////////////////////////////////////////////////////////////////////////////
//           Photomultiplier (PMT) window       
// The refractive index is for lime glass; 
// wavelength dependence is not included and value at 400nm is used.
//////////////////////////////////////////////////////////////////////////////////////

  // Refractive index 

  const G4int N_RINDEX_QUARTZ = 2 ;
  G4double X_RINDEX_QUARTZ[N_RINDEX_QUARTZ] = {h_Planck*c_light/lambda_max, h_Planck*c_light/lambda_min} ; 
  G4double RINDEX_QUARTZ[N_RINDEX_QUARTZ] = {1.54, 1.54};

  G4MaterialPropertiesTable *MPT_PMT = new G4MaterialPropertiesTable();
  MPT_PMT->AddProperty("RINDEX", X_RINDEX_QUARTZ, RINDEX_QUARTZ, N_RINDEX_QUARTZ);

  Quartz->SetMaterialPropertiesTable(MPT_PMT);


//////////////////////////////////////////////////////////////////
//               ACRYLIC Optical properties
//////////////////////////////////////////////////////////////////

// Refractive index 

  const G4int NENTRIES = 11 ;
  G4double LAMBDA_ACRYLIC[NENTRIES] ;


  G4double RINDEX_ACRYLIC[NENTRIES] ;
  G4double ENERGY_ACRYLIC[NENTRIES] ;

// Parameterization for refractive index of High Grade PMMA 

  G4double bParam[4] = {1760.7010,-1.3687,2.4388e-3,-1.5178e-6} ; 
  
  for(G4int i=0;i<NENTRIES; i++){
 
    LAMBDA_ACRYLIC[i] = lambda_min + i*(lambda_max-lambda_min)/float(NENTRIES-1) ;
    RINDEX_ACRYLIC[i] = 0.0 ;

    for (G4int jj=0 ; jj<4 ; jj++)
    {
      RINDEX_ACRYLIC[i] +=  (bParam[jj]/1000.0)*std::pow(LAMBDA_ACRYLIC[i]/nm,jj) ; 
    }

    ENERGY_ACRYLIC[i] =   h_Planck*c_light/LAMBDA_ACRYLIC[i] ;  // Convert from wavelength to energy ;
//  G4cout << ENERGY_ACRYLIC[i]/eV << " " << LAMBDA_ACRYLIC[i]/nm << " " << RINDEX_ACRYLIC[i] << G4endl ;

  }

  G4MaterialPropertiesTable *MPT_Acrylic = new G4MaterialPropertiesTable();
  MPT_Acrylic->AddProperty("RINDEX", ENERGY_ACRYLIC, RINDEX_ACRYLIC, NENTRIES);


// Absorption
  const G4int NENT = 25 ;
  G4double LAMBDAABS[NENT] = 
  {
    100.0,
    246.528671, 260.605103, 263.853516, 266.019104, 268.726105,    
    271.433136, 273.598724, 276.305725, 279.554138, 300.127380,    
    320.159241, 340.191101, 360.764343, 381.337585, 399.745239,    
    421.401276, 440.891724, 460.382172, 480.414001, 500.987274,    
    520.477722, 540.509583, 559.458618,
    700.0    
  } ;

  G4double ABS[NENT] =   // Transmission (in %) of  3mm thick PMMA 
  { 
    0.0000000,
    0.0000000,  5.295952,  9.657321, 19.937695, 29.283491, 
    39.252335, 48.598133, 58.255451, 65.109039, 79.439247,
    85.669785, 89.719627, 91.277260, 91.588783, 91.900307,
    91.588783, 91.277260, 91.277260, 91.588783, 91.588783,
    91.900307, 91.900307, 91.588783,
    91.5
  } ;


  MPT_Acrylic->AddProperty("ABSLENGTH", new G4MaterialPropertyVector()) ;
  for(G4int i=0;i<NENT; i++){
    G4double energy    = h_Planck*c_light/(LAMBDAABS[i]*nm) ;
    G4double abslength ;

    if (ABS[i] <= 0.0) {
      abslength = 1.0/kInfinity ;
    }
    else {
      abslength = -3.0*mm/(std::log(ABS[i]/100.0)) ;
    }

    MPT_Acrylic->AddEntry("ABSLENGTH", energy, abslength);

  }

  Acrylic->SetMaterialPropertiesTable(MPT_Acrylic);
  

//////////////////////////////////////////////////////////////////

  G4cout << *(G4Material::GetMaterialTable()) << G4endl ;

}
//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

G4VPhysicalVolume* UltraDetectorConstruction::ConstructMirror(G4VPhysicalVolume *World_phys){

  G4double Mirror_x = 40.0*cm;
  G4double Mirror_y = 40.0*cm;
  G4double Mirror_z = 1*cm;

  G4Box * boxMirror = new G4Box("Mirror",Mirror_x,Mirror_y,Mirror_z);

  // Get Air pointer from static funcion - (G4Material::GetMaterial)

G4String name;
G4Material *Al = G4Material::GetMaterial(name = "Aluminum");
G4LogicalVolume *logMirror ;
logMirror  = new G4LogicalVolume(boxMirror,Al,"Mirror",0,0,0);


G4ThreeVector SurfacePosition = G4ThreeVector(0*m,0*m,1.5*m) ;

// Rotate reflecting surface by 45. degrees around the OX axis.

G4RotationMatrix *Surfrot = new G4RotationMatrix(G4ThreeVector(1.0,0.0,0.0),-pi/4.);

G4VPhysicalVolume *physMirror ;
physMirror = new G4PVPlacement(Surfrot,SurfacePosition,"MirrorPV",logMirror,World_phys,false,0);

G4VisAttributes* SurfaceVisAtt = new G4VisAttributes(G4Colour(0.0,0.0,1.0));
SurfaceVisAtt->SetVisibility(true);
SurfaceVisAtt->SetForceWireframe(true);
logMirror->SetVisAttributes(SurfaceVisAtt);


//////////////////////////////////////////////////////////////////////////////////////////
//   Optical properties of the interface between the Air and Reflective Surface
//   For Mirror, reflectivity is set at 95% and specular reflection is assumed.


G4OpticalSurface *OpticalAirMirror = new G4OpticalSurface("AirMirrorSurface");
OpticalAirMirror->SetModel(unified);
OpticalAirMirror->SetType(dielectric_dielectric);
OpticalAirMirror->SetFinish(polishedfrontpainted);

const G4int NUM = 2;
G4double XX[NUM] = {h_Planck*c_light/lambda_max, h_Planck*c_light/lambda_min} ; 
G4double ICEREFLECTIVITY[NUM]      = { 0.95, 0.95 };

G4MaterialPropertiesTable *AirMirrorMPT = new G4MaterialPropertiesTable();
AirMirrorMPT->AddProperty("REFLECTIVITY", XX, ICEREFLECTIVITY,NUM);
OpticalAirMirror->SetMaterialPropertiesTable(AirMirrorMPT);



new G4LogicalBorderSurface("Air/Mirror Surface",World_phys,physMirror,OpticalAirMirror);

 return physMirror  ; 

}

//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

G4VPhysicalVolume* UltraDetectorConstruction::ConstructGround(G4VPhysicalVolume *World_phys){

  G4double Ground_x = 40.0*cm;
  G4double Ground_y = 40.0*cm;
  G4double Ground_z = 1*cm;

  G4Box * boxGround = new G4Box("Ground",Ground_x,Ground_y,Ground_z);

  // Get Air pointer from static funcion - (G4Material::GetMaterial)

G4String name;
G4Material *Al = G4Material::GetMaterial(name = "Aluminum");
G4LogicalVolume *logGround ;
logGround  = new G4LogicalVolume(boxGround,Al,"Ground",0,0,0);


G4ThreeVector SurfacePosition = G4ThreeVector(0*m,0*m,1.5*m) ;

// Rotate reflecting surface by 45. degrees around the OX axis.

G4RotationMatrix *Surfrot = new G4RotationMatrix(G4ThreeVector(1.0,0.0,0.0),-pi/4.);

G4VPhysicalVolume *physGround ;
physGround = new G4PVPlacement(Surfrot,SurfacePosition,"GroundPV",logGround,World_phys,false,0);

G4VisAttributes* SurfaceVisAtt = new G4VisAttributes(G4Colour(0.0,0.0,1.0));
SurfaceVisAtt->SetVisibility(true);
SurfaceVisAtt->SetForceWireframe(true);
logGround->SetVisAttributes(SurfaceVisAtt);


//////////////////////////////////////////////////////////////////////////////////////////
//   Optical properties of the interface between the Air and Reflective Surface
//   For Ground, reflectivity is set to 95% and diffusive reflection is assumed.


G4OpticalSurface *OpticalAirGround = new G4OpticalSurface("AirGroundSurface");
OpticalAirGround->SetModel(unified);
OpticalAirGround->SetType(dielectric_dielectric);
OpticalAirGround->SetFinish(groundfrontpainted);

 const G4int NUM = 2;
G4double XX[NUM] = {h_Planck*c_light/lambda_max, h_Planck*c_light/lambda_min} ; 
G4double ICEREFLECTIVITY[NUM]      = { 0.95, 0.95 };

G4MaterialPropertiesTable *AirGroundMPT = new G4MaterialPropertiesTable();
AirGroundMPT->AddProperty("REFLECTIVITY", XX, ICEREFLECTIVITY,NUM);
OpticalAirGround->SetMaterialPropertiesTable(AirGroundMPT);


new G4LogicalBorderSurface("Air/Ground Surface",World_phys,physGround,OpticalAirGround);

 return physGround  ; 

}



//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....

G4VPhysicalVolume* UltraDetectorConstruction::ConstructUVscope(G4VPhysicalVolume *World_phys)
{

  //    ------------- Volumes --------------
  
  ////////////////////////////////////////////////////////////////////////////////////////////////////////
  
  G4cout << "#                                                    #" << G4endl ;  
  G4cout << "#           Building the Telescope    ...            #" << G4endl ;  
  G4cout << "#                                                    #" << G4endl ;  
  
  /////////////////////////////////////////////////////////////
  // UVscope housing is a cylinder made of 1 mm thick aluminum
  /////////////////////////////////////////////////////////////
  
  G4double UVscopeHeight    = 1030.0*mm ;
  G4double UVscopeDiameter  = 518.0*mm ;
  G4double UVscopeThickness = 1.0*mm   ;
  G4double UVscopeBaffle    = 514.0*mm ; 
  
  G4double UVscopeInnerRadius = UVscopeDiameter/2.0-UVscopeThickness ;
  G4double UVscopeOuterRadius = UVscopeDiameter/2.0 ; 
  
  G4ThreeVector UVscopePosition = G4ThreeVector(0.0*m,0.0*m,-1.0*m) ;
  G4String name;
  G4Material* Al = G4Material::GetMaterial(name = "Aluminum");
  
  
  G4Tubs *solidUVscope = 
    new G4Tubs("UVscopeSolid",UVscopeInnerRadius,UVscopeOuterRadius,UVscopeHeight/2.0,0.0,twopi) ;
  G4LogicalVolume *logicUVscope =
    new G4LogicalVolume(solidUVscope,Al,"UVscopeLV",0,0,0);
  G4VPhysicalVolume *physicalUVscope =
    new G4PVPlacement(0,UVscopePosition,"UVSCopePV",logicUVscope,World_phys,false,0);


  //////////////////////////////////////
  // Back cover of the UVscope cylinder
  //////////////////////////////////////

  G4Tubs *solidUVscopeBack = 
    new G4Tubs("UVscopeBackSolid",0.0,UVscopeOuterRadius,UVscopeThickness/2.0,0.0,twopi) ;

  G4LogicalVolume *logicUVscopeBack = 
    new G4LogicalVolume(solidUVscopeBack,Al,"UVscopeBackLV",0,0,0);

  G4ThreeVector UVscopeBackPosition ;
  UVscopeBackPosition =  UVscopePosition+G4ThreeVector(0.0*mm,0.0*mm,-(UVscopeHeight/2.0+UVscopeThickness/2.0)) ;
  G4VPhysicalVolume *physicalUVscopeBack = 
    new G4PVPlacement(0,UVscopeBackPosition,"UVscopeBack",logicUVscopeBack,World_phys,false,0);



  ////////////////////////////////////////////////////////////////////////////////////////////////////////

  G4cout << "#                                                    #" << G4endl ;  
  G4cout << "#           Building the Fresnel lens ...            #" << G4endl ;  
  G4cout << "#                                                    #" << G4endl ;  

  G4double      LensDiameter        = 457*mm ; // Size of the optical active area of the lens.
  G4int      LensNumOfGrooves    = 13 ;
  //G4int      LensNumOfGrooves    = 129 ;
  //G4int      LensNumOfGrooves    = 1287 ;

  G4double      LensBorderThickness = 2.8*mm ;     // Thickness of the border area. 
  G4double      LensFocalLength     = 441.973*mm ; // This parameter depends on the lens geometry, etc !!
  G4Material   *LensMaterial        = G4Material::GetMaterial(name = "Acrylic") ;
  G4ThreeVector LensPosition        = UVscopePosition+G4ThreeVector(0.0*mm,0.0*mm,UVscopeHeight/2.0-UVscopeBaffle) ;


  FresnelLens = new UltraFresnelLens(LensDiameter,LensNumOfGrooves,LensMaterial,World_phys,LensPosition) ;


  ///////////////////////////////////
  // Lens supporting ring (aluminum)
  ///////////////////////////////////

  G4Tubs *solidLensFrame = new G4Tubs("LensFrame",LensDiameter/2.0,UVscopeInnerRadius,LensBorderThickness/2.0,0.0,twopi) ;
  G4LogicalVolume *logicLensFrame = new G4LogicalVolume(solidLensFrame,Al,"LensFrameLV",0,0,0);

  G4ThreeVector LensFramePosition ;
  LensFramePosition = LensPosition+G4ThreeVector(0.0*mm,0.0*mm,-((FresnelLens->GetThickness())/2.0+solidLensFrame->GetDz())) ;

  G4VPhysicalVolume *physicalLensFrame =
    new G4PVPlacement(0,LensFramePosition,"LensFramePV",logicLensFrame,World_phys,false,0);

  ////////////////////////////////////////////////////////////////////////////////////////////////////////


  G4cout << "#                                                    #" << G4endl ;  
  G4cout << "#         Building the photomultiplier ...           #" << G4endl ;  
  G4cout << "#                                                    #" << G4endl ;  


  // Photomultiplier window is a spherical section made of quartz

  G4double PMT_thick   =   1.0*mm ; // Thickness of PMT window
  G4double PMT_curv    =  65.5*mm ; // Radius of curvature of PMT window
  G4double StartTheta  = (180.0-31.2)*pi/180. ;
  G4double EndTheta    = 31.2*pi/180. ;

  G4Sphere *solidPMT ;
  solidPMT = new G4Sphere("PMT_solid",PMT_curv-PMT_thick,PMT_curv,0.0,twopi,StartTheta,EndTheta);

  G4Material* Quartz = G4Material::GetMaterial(name = "Quartz");
  logicalPMT = new G4LogicalVolume(solidPMT,Quartz,"PMT_log",0,0,0);


  // Place PMT is at Lens Focus

  G4ThreeVector PMTpos = LensPosition + G4ThreeVector(0.0*cm,0.0*cm,-(LensFocalLength+PMT_curv)) ;

  // Rotate PMT window through the axis OX by an angle = 180. degrees

  G4RotationMatrix *PMTrot = new G4RotationMatrix(G4ThreeVector(1.0,0.0,0.0),pi);
  new G4PVPlacement(PMTrot,PMTpos,"PMT1",logicalPMT,World_phys,false,0);

 
  G4VisAttributes* PMTVisAtt   = new G4VisAttributes(true,G4Colour(0.0,0.0,1.0)) ;   
  logicalPMT->SetVisAttributes(PMTVisAtt);

  //////////////////////////////////////////////////////////////////////////////////////////
  //   Optical properties of the interface between the Air and the walls of the 
  //   UVscope cylinder (5% reflectivity)


  G4cout << "#    Defining interface's optical properties  ...    #" << G4endl ;  
  G4cout << "#                                                    #" << G4endl ;  


  G4OpticalSurface *OpticalAirPaint = new G4OpticalSurface("AirPaintSurface");
  OpticalAirPaint->SetModel(unified);
  OpticalAirPaint->SetType(dielectric_dielectric);
  OpticalAirPaint->SetFinish(groundfrontpainted);

  const G4int NUM = 2;
  G4double XX[NUM] = {h_Planck*c_light/lambda_max, h_Planck*c_light/lambda_min} ; 
  G4double BLACKPAINTREFLECTIVITY[NUM]      = { 0.05, 0.05 };
  //G4double WHITEPAINTREFLECTIVITY[NUM]      = { 0.99, 0.99 };

  G4MaterialPropertiesTable *AirPaintMPT = new G4MaterialPropertiesTable();
  AirPaintMPT->AddProperty("REFLECTIVITY", XX, BLACKPAINTREFLECTIVITY,NUM);
  OpticalAirPaint->SetMaterialPropertiesTable(AirPaintMPT);

  //OpticalAirPaint->DumpInfo();

  new G4LogicalBorderSurface("Air/UVscope Cylinder Surface",World_phys,physicalUVscope,OpticalAirPaint);

  new G4LogicalBorderSurface("Air/LensFrame Surface",World_phys,physicalLensFrame,OpticalAirPaint);

  new G4LogicalBorderSurface("Air/UVscope Back Cover Surface",World_phys,physicalUVscopeBack,OpticalAirPaint);


  /////////////////////////////////////////////////////////////////////////////////////


  G4VisAttributes* LensVisAtt  = new G4VisAttributes(G4Colour(1.0,0.0,0.0)) ;   // Red
  LensVisAtt ->SetVisibility(true);


  if (FresnelLens){
    FresnelLens->GetPhysicalVolume()->GetLogicalVolume()->SetVisAttributes(LensVisAtt);
  }

  G4VisAttributes* UVscopeVisAtt  = new G4VisAttributes(G4Colour(0.5,0.5,0.5)) ;   // Gray
  UVscopeVisAtt ->SetVisibility(true);

  physicalUVscope     ->GetLogicalVolume()->SetVisAttributes(UVscopeVisAtt);
  physicalUVscopeBack ->GetLogicalVolume()->SetVisAttributes(UVscopeVisAtt);
  physicalLensFrame   ->GetLogicalVolume()->SetVisAttributes(UVscopeVisAtt);

  /////////////////////////////////////////////////////////////////////////////////////

  G4cout << "#                                                    #" << G4endl ;  
  G4cout << "#               UVscope is built ! ...               #" << G4endl ;  
  G4cout << "#                                                    #" << G4endl ;  

  return physicalUVscope;
}


//....oooOO0OOooo........oooOO0OOooo........oooOO0OOooo........oooOO0OOooo....