Dear FLUKA users and experts!
I want to simulate the proton beam bombarding the water model and record the flux energy spectrum of secondary particles (neutrons and gamma rays). In the program, I choose to USRTRACK and USRBDX cards are selected. I want to ask a question: if these two cards are used in the program, do I need to modify the relevant.f(such as ustsuw.f or usxsuw.f) program.
When I look at the relevant PPT, I see the introduction