Bremsstrahlung Threshold as function of Z

Hi!

I’ve been struggling to get my code to simulate bremsstrahlung conversion for 90 keV electrons. The electrons are incident on a tantalum target, where this process should occur. This occurs as expected until 94 keV, below which, no x-rays are produced. If I change the material, this threshold changes (i.e. I do see bremsstrahlung interactions at 90 keV with a hafnium target, for example).

I’ve enhanced x-ray production with event biasing, but it appears as though this process just does not occur below 94 keV if my target is made of tantalum. I have no ideas at all what may cause this, or how to fix, so any advice would be appreciated!

hello,

for bremsstrahlung gamma threshold the only method is to reduce cut in range. How to do this is shown in many examples, please, have a look into $G4INSTALL/examples/extended/electromagnetic/TestEm5

VI