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None Elliptical Mirror reflects but kill photons 

Keywords: ellipsoid boolean solid mirror
Forum: Geometry
Date: 20 Feb, 2007
From: Whitney Armstrong <whit@temple.edu>

I have created an elliptical mirror like this:

  /// Ellipsoid 
  G4RotationMatrix * toroidRot = new G4RotationMatrix;
    toroidRot->rotateY(pi/700);
    toroidRot->rotateZ(pi/900);

  G4Ellipsoid * ellipsoidMirrorOutside = new G4Ellipsoid("farmirror Ellipsoid outside", 
	farToroidalAxisRadius+farToroidalTubeRadius+mirrorThickness , 
	farToroidalTubeRadius+mirrorThickness, 
	farToroidalAxisRadius+ farToroidalTubeRadius+mirrorThickness,
	-100*cm,
	farToroidalAxisRadius+farToroidalTubeRadius+mirrorThickness);

  G4Box* farMirrorBox2 = new G4Box("nearMirrorBox", xFarMirrorBox/2, yFarMirrorBox/2, 
  farToroidalAxisRadius+farToroidalTubeRadius+mirrorThickness);

  G4IntersectionSolid * outerPiece = new G4IntersectionSolid("3mm glass elliptical mirror", 
  farMirrorBox2, ellipsoidMirrorOutside,toroidRot,G4ThreeVector(0,0,-farToroidalAxisRadius-farToroidalTubeRadius));  

  G4Ellipsoid * ellipsoidMirrorInside = new G4Ellipsoid("farmirror Ellipsoid inside", 
	farToroidalAxisRadius+farToroidalTubeRadius, 
	farToroidalTubeRadius,
	farToroidalAxisRadius+farToroidalTubeRadius);

  G4SubtractionSolid * farMirrorGlassElliptical  = new G4SubtractionSolid("Outside - Inside Ellipsoid", outerPiece ,
  ellipsoidMirrorInside,toroidRot,G4ThreeVector(0,0,-farToroidalAxisRadius-farToroidalTubeRadius) );

It works ... ALMOST. That is it reflects properly and looks right, BUT the reflected photons do not interact and are killed once it reaches the edge of the box. Look here http://astro.temple.edu/~whit/badmirror.jpg .

When I swap the solid with a spherical mirror it works fine!! This mirror is constructed similarly:

// Temporary Far Spherical Mirror 
  G4Sphere * farMirrorSphere = new G4Sphere("SphericalMirrorfar", farMirrorRadius, farMirrorRadius+mirrorThickness,0,360*deg,0,90*deg);

  G4Box* farMirrorBox = new G4Box("farMirrorBox", xFarMirrorBox/2, yFarMirrorBox/2,farMirrorRadius+2*mirrorThickness);

  G4IntersectionSolid * farMirrorGlass = new G4IntersectionSolid("3mm thick glass spherical mirror far", 
  farMirrorBox, farMirrorSphere,0,G4ThreeVector(0,0,-farMirrorRadius));

Do you have any idea why this would happen????

Thanks in advance!

-Whit

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1 None: Re: Elliptical Mirror reflects but kill photons   (Vladimir Grichine - 22 Feb, 2007)
1 None: Re: Elliptical Mirror reflects but kill photons   (Whitney Armstrong - 22 Feb, 2007)
3 None: Re: Elliptical Mirror reflects but kill photons   (Whitney Armstrong - 27 Feb, 2007)
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