Sorry to bother, I have a couple of questions. How do I go from the number of particles emitted by the source to the mAs of my spectrum? And also when I use userbin to calculate the dose, does fluka directly generate the actual dose value in the region I selected?
Thanks for your help.
Dear Andrea,
in general, FLUKA scoring divides by the number of simulated primary particles. So, particle fluence or dose in an USRBIN map is calculated for 1 source particle. A normalization factor should be introduced to obtain data in required units and for required source intensity. E.g. plotting of data, Norm field for USRBIN plot, Plot->Y for USR-1D plot of USRBDX scoring card, in the Plot tab.
Also, manually calculated volume (area) of the region (boundary) can be introduced in some scoring cards referring to regions. Otherwise, the result will not be divided accordingly (but this can anyway be easily done at post-processing level).
Also, pay attention for the output units used by FLUKA, it changes depending on the type of scoring you select.
For more details https://indico.cern.ch/event/656336/contributions/2729627/attachments/1552510/2439699/Scoring.pdf
Best regards,
Illia
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Since, as @illia.zymak indicated, FLUKA results are normalized to ONE primary particle, you have to multiply them by your real particle current/intensity (e.g. retrieving the number of primary electrons from the respective current specification in mA).
If you use a Cartesian or cylindrical mesh, you get the dose spatial distribution in GeV/g per one primary particle (averaged over each volumetric bin).
If you use the region mesh, you get instead a value in GeV*cm3/g, which has to be divided by the region volume in order to represent the average dose over the considered region per one primary particle.
Let me recall in addition that the exception to the standard normalization to one primary particle is represented by activation studies where the results are normalized to the input IRRPROF.
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