Hi everyone, a new user of Fluka here. I am trying to simulate a very basic problem with computing dose and diff flux at a certain location from the shielding in a simplistic accelerator geometry. The incident particle beam is say 250 MeV/u Ca-40. It is being fragmented by target and there is shielding of concrete/steel around. I am trying to compute dose and neutron/photon fluence at a certain distance from the shielding and trying to benchmark my results with PHITS.
My question was what PHYSICS cards should be useful here? I know it sounds a very generic question. I am using IONTRANS and DELTARAY cards to begin with. What should be the other cards that might be important for this application? Is the EMF card analogous to the EGS5 in PHITS? I am using ‘HADRONTHERAPY’ as default in this case. Any other cards that might be important for heavy ion transport and computation of neutron/photon flux and total dose?
thank you for your question and welcome to the Forum.
From the general description of your needs, I suggest you use the PRECISIO defaults, not the HADROTHErapy one. Since your source particles will be HEAVYION (and you will specify the A and Z of the projectile via the HI-PORPE card) there is no need for the IONTRANS.
There shouldn’t be a need for the DELTARAY card: you can consult the default values on the FLUKA manual.
Concerning the PHYSICS settings you may want to switch on coalescence and evaporation if residual nuclei and spectra of light fragments are of interest (see the lecture at the FLUKA course on hadronic interactions).
The EMF card switches on or off the electron, positron, and photon transport in FLUKA: by default their transport is active. Having EMF off corresponds to the PHITS parameter negs=0. The thresholds for production and transport of electrons, positrons and photons are controlled by the EMFCUT card (see for example the lecture at the FLUKA course on EM thresholds): this card is somewhat equivalent to the parameters emin(12), emin(13). and emin(14) of PHITS. Pay attention that the default energy unit in FLUKA is GeV not MeV and the default values of the thresholds for photons are not the same.