Help with beginner exercise: EMFCUT, DELTARAY, and preprocessor setup

Flair
1

Versions

FLUKA:4-5.1
Flair:3.4-5.2
Operating system:Ubuntu 24.04.4 LTS

Description

Hi everyone,

I am learning FLUKA and Flair, and I am having trouble completing an exercise from the beginner course.
Here are the guidelines for the exercise:

Input Configuration:

  • 10 MeV electron beam

  • Circular beam with 2 mm radius

  • 5 mm radius target split into three layers, each 50 μm thick

  • Layer materials: H2O – Pb – Al

  • Thin layers require high tracking precision, so set DEFAULTS PRECISIO (should already be set)

  • Define three preprocessor variables: HI-THR, LOW-THR, VLOW-THR

  • USRBIN scoring DOSE over the entire target: 1 μm bins in Z, 1 μm bins in R, unformatted unit 55

  • Add EMFCUT and DELTARAY cards:

  • Set both production and transport thresholds in all materials.

    (Hint: use @LASTMAT / @LASTREG as needed to refer to the last material or region)

  • Threshold cases:

#if HI-THR
  photons: 1 keV , electrons: 1 MeV kinetic energy, FUDGEM=1
#elif LOW-THR
  photons: 1 keV , electrons: 100 keV kinetic energy, FUDGEM=1
#elif VLOW-THR
  photons: 1 keV , electrons: 10 keV kinetic energy, FUDGEM=0.5
#endif
  • Note: The default electron threshold is 100 keV in the case of PRECISIOn.
  • Reminder: Stopping powers and ranges for electrons, protons, and He ions are available on the NIST webpage: NIST: Introduction of ESTAR, PSTAR, and ASTAR

My Issue:

I have attached my current project files (.flair / .inp) as well as an image of the expected results I am trying to achieve.
The problem is that I cannot get the simulation to run properly. Either FLUKA gets stuck running indefinitely, or I encounter multiple definition/formatting errors, and I cannot figure out what is going wrong with my setup.
Any help or guidance would be greatly appreciated. Thank you in advance!

Input files

aula09.inp (1.9 KB)

aula09.flair (2.5 KB)

imagem
imagem1420×870 145 KB

3

Hello @bruna.francisco , welcome to the FLUKA forum!

From a first quick look to your input and flair file there does not seem to be any particular issue. For this reason, would you be able to a “.out”, “.log” or “.err” file from within your run directories? You can already have a look since this should give an indication what the error is.

In addition, when opening the Geometry tab in flair there is a warning: your three RCC bodies are touching. It is good practice to use infinite bodies as much as possible. I believe at minimum you would need to define only one RCC body and cut it using two infinite planes to avoid tracking errors (which could be at the basis of your problems). You can find more information on slide 30 of the Geometry I lecture at the last FLUKA Beginner’s course.

Hope this already helps! Best regards,

Andreas