Scoring dose equivalent of particles in a room of air

Dear fluka users and experts,
I have an electron beam of 5.5Gev in a room with dimensions -200<x<200 ,-320<y<320,-500<z<500.
the beam is in the center and has positive direction.I want to calculate the dose equivalent for photons ,electrons and secontary netrons inside the room.the room has air inside and also walls of 50cm depth made of concrete.

the fact is that i can’t score nothing with USRBIN in the inner space of the room which i refer above ,it gives an error all the time. later i also put a small target inside he room but its not the fact of this simulation .i also tried to score in a smaller part of the room for example 50<x<150…but nothing again .i have taken different kind of errors like RC=12 and 2 and 137 ,in the last run it was 2.i thing that something has to do with geometry .
i also tried the usrbin region scoring but i dont think that im using it right ,can you explain it,cause i havent found enought information.
(in this simulation i tried to score photons and electrons and equivalent dose of photons,its just a trial until i see that the simulation works,at the beginning i also had no target)
can you direct me please where might be the mistake?
here is the file
electr_new.flair (2.8 KB)
i want something likethe plots of that example below , the dose eq in the room:

im looking forward for your reply.

Dear Artemis,

the issue is that your dose_eq scoring requests 1000 x 1000 x 4000 bins, which would require ~16 GB of memory and FLUKA can’t allocate that much.

Reducing the bins to 100 x 100 x 400 the simulation runs without any error.

For the USRBIN region based scoring you need to specify a range of regions (based on the order they are defines) where you want to score the (generalized) particle. The step option specifies the steps in the range, i.e. step = 2, if you only want to score in every second region in the specified range. Usually it is left empty.


Thank you very much for your answer.i just was thinking that the bins must be enought as the room is a quite big space,but now its running!
I also want to measure the equivalent dose for secondary neutrons,which i suppose that sould be produced as the energy of the beam is high enought, but usrbin shows no result when scoring particle is neutron.should i use another detector or an extra card ?

Dear Artemis,

you need to use a PHOTONUC card with the Type: ELECTNUC to activate both the photo- and electro-nuclear interactions and produce secondary neutrons with electrons (and photons).


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2 posts were split to a new topic: Scoring neutron does equivalent using an electron beam