Running into errors setting up fluka simulation

Hello! I hope you can help. I am trying to simulate a neutrino interacting in ice (code attached), and count the number of neutrons (and muons if possible) produced from the interaction.

Unfortunately I had some trouble getting things working - it looks like from the error file I may have an issue with defining Aluminium?

I wonder if this is caused by some alignment error, or perhaps something wrong with my understanding of the syntax? Any guidance is greatly appreciated!

Thanks very much!

ice.out (15.1 KB)
ice.err (820 Bytes)
ice.inp (3.5 KB)

Dear @krhfarrag,

The problem is that you used 9 characters in order to name your material and Fluka accepts a maximum length of 8 characters.
Also, when I downloaded your input and loaded it in Flair I also saw some alignment errors. I order to avoid such things, it’s better to use Flair in order to write your input.
There are also some errors in the geometry, but I cannot help you with these since I don’t fully understand the geometry that you have.
You need to assign materials to all regions (you assigned materials only to regions 1,2,3 and 4).

  • I changed the composition for Water and Ice into H2O not H2Be.
  • And I also changed the Unit for scoring to 21.
  • By default, Fluka does not transport neutrinos, so you need to use a Physics card. Please take a look here.

You can find the modified inp file attached to this message, but you still have to change some things in order to reproduce the experiment (geometry and assigning materials).

Best regards,

ice_modif.inp (3.5 KB)

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I am really thankful for your explanations and guidance Mihaela. I’ll try again, this time using Flair as you suggested, and also read up on the information you wrote about cards for neutrinos. Kösz and best wishes :slight_smile:

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Dear krhfarrag, first of all I would join recommendations form Mihaela Parvu. Indeed, it is easier to use Flair GUI unless you have reasons not to do so.

Most problems that you have in the code are syntax and FLUKA programming culture errors, which will be traced and suggested by Flair environment.
For example, there are several things preventing you from running code smoothly:

  • you redefining standard material predefined in Fluka, moreover for definition for materials and compounds you are using codes (numbers) for already existing materials;
  • also you are using codes of existing materials to define compounds; just left fields empty to make Fluka assign codes automatically;
  • there are no assigning of some compounds material (name and density) before setting up their composition, see;
  • there are also some minor syntax problems in assigning of materials to regions,
  • a region cannot be defined by a single plane, as it is a volume in Fluka.

The next important question touched by Mihaela Parvu, is that after you can run your code you have to ensure that your model includes properly configured physics:
1 - to configure neutrino/muons transport as it has been suggested;
2 - to verify, that cross sections of neutrons and especially muons production is sufficiently high for you materials, geometry and number of primaries, but also that important production mechanisms are enabled in your model. Otherwise, you need to use biasing techniques to make probabilities and so, numbers of produced particles detectable. To do so, you need to estimate which channels are dominant for your conditions, e.g. photoproduction of muon pair, electron-electron collision or decay of pions produced by bombardment of nuclei by hadrons.
Also, to understand physics settings of the model better, I would suggest you to score each type of particles separately.

Please do not hesitate to ask me, if some of my comments was not clear.

Best regards,
ice.flair (3.1 KB)
ice.inp (3.2 KB)

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