|Message: Emission from isotropic point source that exits a rectangular window||Not Logged In (login)|
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I need to simulate photons that are emitted from an isotropic point source, but I only need to simulate the ones that are emitted in a direction so that they travel through a rectangular window. I know that GPS has an isotropic angular distribution and that you can limit the angles, but that would give me the equivalent of the exit window being a portion of a sphere centered on the source, not of a flat exit window. Also, I've seen the C++ version of having an isotropic source:
G4double cosTheta = 2*G4UniformRand() - 1., phi = twopi*G4UniformRand(); G4double sinTheta = std::sqrt(1. - cosTheta*cosTheta); G4double ux = sinTheta*std::cos(phi), uy = sinTheta*std::sin(phi), uz = cosTheta; particleGun->SetParticleMomentumDirection(G4ThreeVector(ux,uy,uz));
and I understand I could limit cosTheta and phi to a specific range of values, but again I would get whatever exits a portion of the sphere. Does anybody know how I can limit the isotropic source photons to those that cover a certain delta X and delta Y at a certain R distance from the source? I don't mind having to code it in the PrimaryGeneratorAction and not using GPS, I'm actually more used to the former.
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