I’m having issues defining a detector based on the basic example B4c with G4Tubs instead of G4Box as the solid shapes (I’ve also enlarged the transverse face and increased the number of layers). However, I find significantly different response distributions between the two shapes. When I switch from G4Box to G4Tubs, I set the outer radius to sqrt(2) times the half length of the box face so that the cylinder has a somewhat larger volume than the box. Oddly, the response distribution of the cylindrical calorimeter has a significant (heavy) low energy tail; whereas the rectangular calorimeter has a normally distributed response.
Am I missing something in placing or orienting the solids; is there something more I need to do besides replacing G4Box with G4Tubs?