No score for USRBIN using either BEAM source or RTPLAN

Hello dear FLUKA experts and users,

I hope this message finds you well. I am seeking assistance with a FLUKA simulation issue.
With the valuable help of @vasilis and @wkozlows, I successfully built a phantom using multiple CT slices and defined the organ materials. However, I encountered a problem where the particles do not interact with any organs in the simulation. The situation is that I have an RTplan of a photon source, but FLAIR does not recognize it as a beam. To address this, I manually defined the photon source based on the instructions from the ‘advanced sources’ lecture. Additionally, I used the USRBIN card to evaluate the received lung dose.
Unfortunately, despite these efforts, the simulation results in a dose of 0. You can find the simulation file attached here: 247a2.flair. I also attempted to use a simple BEAM source, as defined in the second attached file (247-1B.flair), but encountered the same issue.

I would be immensely grateful if someone could kindly assist me in resolving this problem.

Thank you very much for your time and consideration.

Best regards
247a2.flair (5.7 KB)
247-1B.flair (5.4 KB)

Dear @ibtissam.zidouh,

You have not uploaded your voxel file, therefore it is not possible to run, and debug, your simulation.

Thank you @amario for your reply. I apologize for the oversight. I have uploaded now the necessary voxel file in DRIVE, here is the link :


Dear Ibtissam,

you don’t score anything, because you beam doesn’t hit the patient. See the arrow marked spot1 on the figure below.


The same also applies for the simple BEAM case



Thank you dear @David and @amario for considering my request.
I actually have no idea about how to show the direction of the beam in the geometry section.
Could you please enlighten me on how to do it?

And regarding the definition of the beam it was done considering the RTplan as shown in the screenshots, I would be extremely grateful if someone could offer their expertise and advise me on the necessary steps to rectify the problem.


Dear @ibtissam.zidouh,

Unfortunately, I cannot help you with the RT plan as I’m not at all an expert on the topic.
But I can answer your first question.

To visualize the beam, you have to select the BEAM in the left panel of the geometry tab:

To make the arrow bigger, you have to increase the scale in the properties-list of the BEAM:

A post was split to a new topic: Beam definition from RTPLAN