Plotting the spectrum as given in the image

[arun.kumar (ARUN KUMAR R M)]

Versions

FLUKA:4.5.1
Flair:4.4.0

Description

I need a plot similar to the above image. both 2nd protons and alpha particles. Input protons i am getting from EPOCH. Basically i need the spectrum of alpha particles and the protons and I also need to measure the angular distribution of the alpha particles (dn/dtheta*dE) (deg/MeV). Which scoring card i should use to get the respective spectrum and the angular distribution ?

Input files

test_3MeV_protons.inp (6.6 KB)

[kltaylor (Kate Louise Taylor)]

Dear Arun,

Thank you for your question.

The answer will depend on the what the angular distribution is relative to:

• If you are looking for an angular distribution in solid angle (sr) with respect to the particles trajectory and the boundary they are crossing then one could use USRBDX

  • USRBDX will provide a particle fluence or current (not particle number)
    • 7.22.88. USRBDX — FLUKA Manual specifically note 2 and 3

• If you are looking for the angular distribution with respect to the beam orientation (or other as specified by user using SDUM), one can use USRYIELD

  • USRYIELD will provide a particle yield
    • 7.22.95. USRYIELD — FLUKA Manual
    • What is the physical meaning of particle yield?

In each option taking care of units (polar angle, solid angle - particle number, yield, current or fluence) to normalise.

Please find in addition the slides on scoring from both the beginner and advanced FLUKA courses, which details both cases with examples.

12_Scoring_II_2025_JRC.pdf

07_Advanced_scoring_2023_Advanced_ANL.pdf

Many thanks,

Katie

[arun.kumar (ARUN KUMAR R M)]

Dear sir,

Thank you for your response. Basically i need a kind of plot attached below.

I have used USRYIELD and obtained the plot as below for different energies. But how to get polar plot as the above image for various energy and with same colorbar. Kindly help me on this regard.

[kltaylor (Kate Louise Taylor)]

Hello @arun.kumar

Depending on the resolution you desire, I would adjust the angular binning in the USRYIELD card accordingly.

To convert the output into the format you’ve requested, I would suggest using a python script. The USRYIELD output format can be found here. 9.5.9. USRYIELD output — FLUKA Manual 7.22.95. USRYIELD — FLUKA Manual

[arun.kumar (ARUN KUMAR R M)]

I have used useryield card. But how to do simultaneous binning of both energy and angle like the above figure ? Can you please help me to get the exactly similar plot like this.

[kltaylor (Kate Louise Taylor)]

Are you experiencing an issue with the USRYIELD input (if so may you share you input file so I could more easily identify the problem), or with processing the output?

If it is regarding the output please consider:

• Converting the output to the above plot is down to data processing, and use of python - FLUKA/flair will not produce a plot exactly like this.
• USRYIELD gives the angle in polar angle, so double check your min/max values reflect this.
• Be cautious about normalisation as I mentioned before.

In your case however, if you are considering the angle relative to the boundary crossing of your target - it may suit you better to use USRBDX.