Dear FLUKA experts,
I was studying material exercise(link is below) in the beginner course-24 recently, and i have defined the material definition (gruyer cheese) completely different than the solution and scored with USRBIN scoring as the same way. The results were seem different in either case (forgive me about not sharing the scoring outputs, they are in different pc and i am far away from it now, but if you request, i can upload later.)
My question is that, does the molecular structure of compound materials etc. effect the scoring options?
Ex: In the example, C3H7NO2(proteins) is defined as 3 carbon atoms, 7 hydrogen atoms, 1 nitrogen atom, and 2 oxygen atoms. But i have defined NO2 first, and then i have used it in the rest molecule definition. Also, the same way for the lipids(CH3(CH2)14COOH). And that caused different proton fluence than defined one in the solution. What is the best way to describe the complex materials?
Both options (directly inputting elements or redefining components) should give the same material definition. If you have different results than it usually indicates that something is wrong with the definition.
Could you share your input file so we can check it?
Thank you for your reply.
If material structure (also, i am wondering the effect of chirality, the bond angle of two molecules etc.) is not effecting the scorings then maybe it is related with density. Because i have defined different material densities than defined ones in the solution.
Still, i have uploaded the input file, in case you would like to check it.
Thank you for this information. I have thought, in next compound card the molecule will be added as 1 molecule with the same atomic ratio.
Additionally, it could be stupid question but i have wondered, i know that FLUKA only considers stoichiometry of the material compositions, molecular geometry is not taken into account by FLUKA, but let’s say, i want to run some simulation with diamond based target how can i implement the lattice structure of diamond into the target? Do i need to implement it by geometrically only? Or is there another way to do it?
Thank you again.
FLUKA doesn’t handle crystal structures(*) on a material level, so graphite and diamond is the same material with different densities. The only difference is you can set specific thermal scattering scross sections for graphite in case of low energy neutrons.
Cheers,
David
* Except the option to transport positively charged hadrons and muons in bent crystals.