Fluka error on spectrum file

Dear fluka user,

I run a simulation, sampling from an energy spectrum (using the command sample_spectrum_momentum_energy) and
source_newgen.f (18.7 KB)
using source_newgen.

IN the end of the 1st cycle, this ERROR appears:

Sampling from spectrum requested

*** Impossible to open file ***
*** on unit 1 *****
Abort called from sample_spectrum_momentum_energy reason Unable to open spectrum file Run stopped!
STOP Unable to open spectrum file

What is the problem?

reactpr new002.out (603.3 KB)
histogram.txt (1.4 KB)
source_newgen.f (18.7 KB)

reactpr new001.out (698.4 KB)

1 Like

Dear Vasilis,

since you didn’t attach your input file, I could test your simulation, but with a dummy FLUKA input, I could try your source routine.

I didn’t encounter any issues with reading the histogram.txt file, please ensure it is copied to the correct directory, especially if you have runs in separate subdirectories.

Furthermore, please update your FLUKA version to the latest 4.3-4. Support will be provided only to the last release.


Here is my input
reactpr new.flair (89.7 KB)

Dear Vasilis,

you need to keep the histogram.txt file where your Flair project file / FLUKA executable is, not in the routines directory.

After putting the file in the correct position, the simulation runs, but it stops due to geometry errors, as can be seen below:


How can i see these errors?
When i zoom there, it doesnt give me any errors.

Dear Vasilis,

you may turn on the synchronize function on the Geoviewer tab of Flair to reset your viewports.

The errors in the geometry are:

  • Missing the air region for cassette 132 between xyp3 and xyp4
  • Cassette 203 is not removed from the body zccbig


One further remark.
The regions: waterin (last zone), and airin (second zone) contain an expression with multiple cylinders removed.
The tracking there will be slow due to the multiple bodies that have to be evaluated on every step.

If you want to speed it up you can artificially segment these zones with a few planes, e.g. YZP(s), so as to result into multiple zones with smaller number of terms.