I’m simulating the gamma ray spectra detected by LaBr3 detector after the impinging of proton beam on the solid water, but the result is so different with the experiment one as shown below:
It seems the DETGEB card was not used, but I checked I have used it in the input file.
Also, the peak in the experimental result had not be reproduced by the calculation,Is there any problem with my input file?
The files are attached below LaBr3_efff.inp (3.4 KB) LaBr3_efff.flair (3.2 KB)
However, your result doesn’t have enough statistics. The quantized steps in count height indicate that the bins only recorded 1, 2, 3 … etc hits.
Unfortunately, I don’t see any way you could increase the speed of your simulation, since the biasing methods are not compatible with the DETECT scoring. You just need to run more primaries.
Dear David,
Really thanks for your reply!
Consider the time consume, I just increase the number of primaries by twice, from 5*10^7 to 10^8, the result (the black one) became better but was still different from the experimental one.
Then I increased the energy of the beam with the same primaries numbers (10^8), from 59.8 MeV to 121.1 MeV, the result (the red one) seems more similar with the experimental one. So I 'm wondering except the statistics (Exp: 10^10 ), I still need to consider the PHYSICS part. Do you have any advise?
The physics settings you are using seem to be fine, but you may want to tweak the Fudgem parameter on the EMFCUT card, according to the manual:
FUDGEM parameter. This parameter rules the contribution of atomic electrons to multiple scattering. For electron production and transport cutoffs larger than 30 keV, it should be set to 1.0, while it should be 0.0 when those cutoffs are below 5 keV. Between 5 and 30 keV, a linear interpolation from 0.0 to 1.0 is recommended.
The difference between the measurement and simulation could be explained by the geometry differences though.
