Six cilyndrical sources of Co-60

Hello, FLUKA experts!
I have the following task. Construct the Co-60 source as six cylinders (each 50 cm long, diam. 2 cm) spaced 100 cm from a common center. The problem is that after I define the source and put them in their places, I cannot make them cylinders, dots only.

How to make each cilyndrical?

Thanks to advance.

HexSrc.flair (3.8 KB)
HexSrc.inp (3.7 KB)

Hello Suvorov,

Most of your input file is perfectly working. Unfortunately, the use of BEAMSPOT special source does not seem sufficient for your case. It allows indeed to define multiple sources in the same simulation, but each of these will not be a volume source, but just a 2D source (appropriate for beams).
In your input file, this means that the z-thickness of your sources is 0.

For your specific case, I would suggest two possible solutions:

  1. You can implement a Fluka user routine source (source.f) where you can manually define your sources.
  2. You can run multiple simulations and merge the final results. Considering the symmetry and the simplicity of the problem, I would strongly suggest this option.

In the latter case, the procedure I would implement is to use a #define card describing the angle. Then, with the BEAMPOS cards, you choose the position and the shape of your source in terms of the angle. Finally, you loop over the angle variable to run different simulations.

I attach here a possible solution. The BEAMAXES card is needed to rotate the FLUKA frame of reference with the one you use in the simulation. Just as final comment, since the radius of the sources is just 1 cm in a fairly large geometry (~1 m), I wouldn’t expect to see a huge difference between the volume and the line source.

HexSrc_dcalzola.inp (2.6 KB)