Dear FLUKA experts,
I saw a similar topic posted here,
USRBDX detector area and fluence comparison to that by USRBIN:
but I still have more questions.
I ran a low energy neutron production simulation with a simple geometry. I invoked two scoring cards - USRBDX and USRBIN. In my geometry, I included a detector box of total surface area, 6cm^2.
The USRBIN scoring card tracks the neutron fluence in a volume of space which exactly covers the volume defined by the detector box.
The USRBDX card scores the one-way differential fluence (no. of solid angle bins equals 1) of neutrons from the region defined by the box to the volume of space outside of it.
I plotted a 2D map of the fluence in Flair. Flair gives me an integrated value. I compared this value with that of the cumulative flux provided at the top of the sum.lis file provided by USRBDX.
Integrated value obtained from USRBIN in Flair: 5.98E-005
Result from USRBDX (without area normalization): 8.7109998E-05 +/- 1.612777
Result from USRBDX (with area normalization): 1.4516667E-05 +/- 1.612777
These values are different, but I know that USRBIN and USRBDX should gave the same result, within statistical uncertainty. Please let me know what might be wrong in my analysis.
Thank you for your guidance.
Kind regards,
Dalini