Issue regarding overlap in etector construction

Geometry, Fields and Transportation
1

So here is the my code for the detector construction, and its showing an overlap with the mother volume

MyDetectorConstruction::MyDetectorConstruction() {
  nCols = 7;
  nRows = 7;
    
  DefineMaterial();

  xWorld = 1.0*m;
  yWorld = 1.05*m;
  zWorld = 2.0*m;
}

MyDetectorConstruction::~MyDetectorConstruction() {}

void MyDetectorConstruction::DefineMaterial()
{
  G4NistManager *nist = G4NistManager::Instance();  

  Ar = new G4Element("Argon", "Ar", 18., 39.948*g/mole);
  O = new G4Element("Oxygen", "O", 8., 15.999*g/mole);
  N = new G4Element("Nitrogen", "N", 7., 14.007*g/mole);

  Aluminium = new G4Material("Al", 2.70*g/cm3, 1);
  Aluminium->AddElement(nist->FindOrBuildElement("Al"), 1);

  Pb = new G4Element("Lead", "Pb", 82., 207.2*g/mole);
  W = new G4Element("Tungsten", "W", 74., 183.84*g/mole);
    
  Air = new G4Material("Air", 1.214*mg/cm3, 3);
  Air->AddElement(N, 75*perCent);
  Air->AddElement(O, 24*perCent);
  Air->AddElement(Ar, 1*perCent);
  PbWO4 = new G4Material("PbWO4", 8.300*g/cm3, 3);
  PbWO4->AddElement(Pb, 1);
  PbWO4->AddElement(W, 2);
  PbWO4->AddElement(O, 2);
}

G4VPhysicalVolume *MyDetectorConstruction::Construct() 
{
    solidWorld = new G4Box("World", 0.5*xWorld, 0.5*yWorld, 0.5*zWorld);
  
    logicWorld = new G4LogicalVolume(solidWorld, Air, "World");

    physWorld = new G4PVPlacement(0, G4ThreeVector(), logicWorld, "World", 0, false, 0, true);

    solidRadiator = new G4Box("solidRadiator", 50.4*cm, 30.4*cm, 121.9*cm);

    logicRadiator = new G4LogicalVolume(solidRadiator, Aluminium,"logicalRadiator");

    fScoringVolume = logicRadiator;

    physRadiator = new G4PVPlacement(0, G4ThreeVector(0.,0.,-129.0*cm), logicRadiator, "physRadiator", logicWorld, false, 0, true);
 
    G4double xsize(2.2*cm), ysize(2.2*cm), zsize(23.6*cm);

    solidDetector = new G4Box("Detector", 0.5*xsize, 0.5*ysize, 0.5*zsize);

    logicDetector = new G4LogicalVolume(solidDetector, PbWO4, "Detector");

  G4double xpos = -0.5 * xsize * (nRows - 1);
  G4double zpos = (+25.0 + 121.9)*cm + 0.5*zsize;
  for (G4int i=0; i < nRows; i++) {
    G4double ypos = -0.5 * ysize * (nCols - 1);
    for (G4int j=0; j < nCols; j++) {
      G4int copy = i * 10 + j;
      new G4PVPlacement(0, G4ThreeVector(xpos, ypos, zpos), logicDetector, "Detector", logicWorld, false, copy, true);
      ypos += ysize;
    }
    xpos += xsize;
  }
  return physWorld;
}

The output sown in the terminal is the following

Overlap with mother volume !
          Overlap is detected for volume Detector:65 (G4Box) with its mother volume World (G4Box)
          protrusion at mother local point (58.6427,53.2418,1705) by 70.5 cm  (max of 1000 cases)
NOTE: Reached maximum fixed number -1- of overlaps reports for this volume !
*** This is just a warning message. ***
-------- WWWW -------- G4Exception-END --------- WWWW -------

Checking overlaps for volume Detector:66 (G4Box) ... 
-------- WWWW ------- G4Exception-START -------- WWWW -------
*** G4Exception : GeomVol1002
      issued by : G4PVPlacement::CheckOverlaps()
Overlap with mother volume !
          Overlap is detected for volume Detector:66 (G4Box) with its mother volume World (G4Box)
          protrusion at mother local point (57.8513,55.8805,1705) by 70.5 cm  (max of 1000 cases)
NOTE: Reached maximum fixed number -1- of overlaps reports for this volume !
*** This is just a warning message. ***
-------- WWWW -------- G4Exception-END --------- WWWW -------

Please help

2

Please check the formatting of your code as whilst it looks like your following the guide (How to post code snippets - #9), and backticks “`” have been replaced with quotes.

3

I have done the necessary changes.

4

This is hard to read. One major issue is the z coordinates here.

zWorld = 2.0*m;
solidWorld = new G4Box("World", 0.5*xWorld, 0.5*yWorld, 0.5*zWorld);

Your world has extent of (-1, 1) meter, However,

solidRadiator = new G4Box("solidRadiator", 50.4*cm, 30.4*cm, 121.9*cm);
physRadiator = new G4PVPlacement(0, G4ThreeVector(0.,0.,-129.0*cm), logicRadiator, "physRadiator", logicWorld, false, 0, true);

Your radiator volume is centered outside the world volume at -1.29m. Meanwhile, the detector is outside the world volume on the other side:

G4double zpos = (+25.0 + 121.9)*cm + 0.5*zsize;

The copy ids are going to have gaps:

G4int copy = i * 10 + j;

Lastly, I would always try to put some buffer around detector elements to avoid setting off overlap checks. Even in reality you can’t machine down to 0 gap between elements. So I’d do, as an example:

yspacing = ysize + (0.1 * mm);

to

ypos += yspacing;

You’d have to recenter it (and repeat for x-direction) but that should cover a lot of the obvious bases here.