Gaussian broadened peak in HPGe at 1.33 MeV

Dear FLUKA experts,

I have modelled HPGe geometry (by optimizing various detector geometry parameters) in FLUKA and used Gaussian broadening parameters obtained from experiment. While comparing the peak region, I found the FLUKA output is not very smooth. Please note, if we take total counts under the peak and estimate full energy peak efficiency, I am getting similar values as that of experiment. I am wondering if there is any way to improve the smoothness of broadening ? Also, I have noticed the smoothness is more for a Cs 137 source as compared to a Co 60 source (see the attached two figures). I have used a history of 1.25E+7 for 5 cycles in both the cases.

Regards,
Riya

Dear @riya,
It’s difficult to say anything for two main reasons:
1-You didn’t share the inputfile, so we don’t know what you did.
2-Most importantly, even if you had shared the input, we don’t know the details of the experiment. A plausible option would be that the geometry is not detailed enough to replicate the data.
It would be complicated for someone not involved in the experiment to explain the difference.

Thank you @amario for the response.