Hello! Say me please, in Cerenkov.cc, the ChR spectrum is defined as pmin+G4UniformRandom()*dp, where pmin is the minimal photon impulse, dp=pmax-pmin, G4UniformRandom - is the random number generator from 0 to 1. But as I know for electrons ChR spectrum is defined Tamm-Frank equation: is dW/d(lambda)e^2/c^2 ( 1 - 1/(beta^2 n^2) 1/(lambda^3) )d(lambda). Have Geant4 more simple model? If it’s true, maiby, someone made Tamm-Frank model in GEANT4?
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Hello,
In G4Cerenkov it is assumed , that during the step beta changed only a little, so average beta is used. This is is a natural assumption, because making a Cerenkov light simulation for large step when beta is changed significantly brings problem as to sample a correct spectrum and gamma directions. We always recommend to limit step size inside radiators.
VI