Dose to blood vessels due to alpha and beta radiation

Dear FLUKA experts,

I want to simulate the dose to blood vessels due to alpha radiation.
If I understand correctly, the penetration depth of alpha particles in a tissue is of several microns, while the thickness of the layers in the big blood vessels is about several hundreds of microns.
I want to use a simplified geometry of concentric cylinders corresponding to the different layers of the blood vessel.

  1. What is the resolution of FLUKA? Does it depend on the radiation type? (alpha, beta, etc?)
  2. From your experience, how can I obtain the right materials’ atomic structure so I can implement it in FLUKA? I found information about the physical dimensions of each layer.

Thank you kindly in advance,
Hen Shukrun

Dear Rachel ,

FLUKA transport limits are indicated in the manual and are motivated by the condensed history approximation for charged particle tracking.
You may find interesting also these slides from the FLUKA course about EM interactions and transport of charged particles.

Not sure about your second question. For sake of clarity, FLUKA assumes only homogeneous media (with a single exception that is of no interest for your application). It’s user’s responsibility to define the composition and density of any user-defined materials.
FLUKA has a list of predefined element/compounds and Flair provides a library of materials.

Hope this could help.

Best regards, Luigi

Dear @luillo ,
Thank you kindly for your answer.
Based on the transport limits, how can I calculate the reliable resolution for my simulation?
I want to get the dose distribution in a tissue using USRBIN. Can the bin size be defined as 0.1 micrometer^3, or is it too small?

Thank you in advance,
Hen Shukrun

Dear @rachel.hen.shukrun ,

guidelines are given in the slides posted in my previous post (from page 29).
I also recommend to switch on the single scattering with the MULSOPT card.

Best regards, Luigi

Dear @luillo ,
Thank you very much for your help.
Following your recommendation I add the the MULSOPT card and adjusted the USRBIN detector.
I am adding my .inp and .flair files here.

I have two questions:

  1. based on your experience, were the MULSOPT card and the detectors defined correctly? Is there a need to take another consideration into account?
  2. Is there a way to score only certain angle range in R-Phi-Z USRBIN?

Thank you in advance,
Hen Shukrun
AlphaVeins.flair (15.0 KB)
AlphaVeins.inp (4.7 KB)

Hello @rachel.hen.shukrun

see my answers inline



Cheers Luigi