Regarding the issue of missing high-energy PKAs

[131415248 (Yingming Sang)]

Dear FLUKA experts,

Recently, when calculating PKA energy spectra using mgdraw.f, my post-processing of the raw data is as follows: I bin the obtained PKAs into corresponding energy regions based on a predetermined energy grid; then divide by the product of my simulation particle count and number of cycles, multiply by the total flux of the incident neutron spectrum, and divide by the target volume. The resulting PKA counts in the high-energy region are far lower than expected. What could be the possible reasons?

Since my incident particles are low-energy neutrons, according to the mgdraw.f documentation, my reaction tracking is limited to icode=300. I note that icode=100 corresponds to elastic scattering. Does the icode=300 description encompass elastic scattering reactions?

Thanks a lot in advance

Best regards
pka.flair (4.9 KB)
mgdraw_gen.f (10.1 KB)

[ceruttif (Francesco Cerutti)]

@131415248

Does the icode=300 description encompass elastic scattering reactions?

Yes, namely elastic interactions by low-energy neutrons (the word ‘reaction’ implies the inelastic nature of the interaction).

@131415248

The resulting PKA counts in the high-energy region are far lower than expected. What could be the possible reasons?

Most likely your post-processing. By the way, where does your ‘expected’ curve come from?
Please upload your source routine too, and the mgdraw routine that you are actually using, since the one indicated in the flair file has a different name.
Also, note that PKAs - as repeatedly discussed on the occasion of your previous posts - shall be looked at in the fheavy stack, being their energy tkheav(1).