To simulate the detection efficiency of HPGe detector with gamma incoming beam source
The detector geometry incudes two scenarios: with an aluminium cap or without the aluminium cap
The gamma source is investigating in the range between 20keV to 4MeV. And the source is using particle gun (pencil beam) and isotropic source, by applying 'Particle Gun' and 'General Particle Source', respectively.
The detector itself consists of active Ge area and the dead layer. Where a hole in the center of the Ge crystal area as for 'cold finger' or cooling for the detector in reality, Here in the simulation we just keep it as a hole.