I want to get the production rates of H3 in germanium from the effects of cosmic-rays(neutrons) based on the geant4 and cosmic-ray Shower Library (CRY).
I noticed that production mechanisms was like as followings:
where
Ri ----- production rate
i ----- a radioactive isotope(H3)
Nj ----- number of stable target isotope j(germanium)
Φk ---- flux of cosmic-ray particle k(neutrons)
σijk ----- production cross section of radioactive isotope i(H3) produced by cosmic-ray particle k(neutron) on target isotope j(germanium).
ma2018.pdf (1.1 MB)
And I also noticed those words from above article:
“Secondary nuclides produced by every event were recorded, and the number of each nuclide was counted after an entire run. The cosmogenic production rate of each nuclide was calculated by adding a weight of flux value to the number of this nuclide, and the result was normalized to the unit of kg−1 d−1.”
So, to record the secondary particles. I write following words in my code. however, because of my poor level of cpp, I am not sure if it is wrong or right. Thank you very much for helping me 
HistoManager1.cc (5.2 KB)
What is more, I do not know what is the Φk exactly. After I conducted a shield on germanium. Φk mean the flux which I put on geant4 ? the cell flux in germanium or something else?
And where to find the cross-section datum? It seems that different physical lists in geant4 will cost the different results. It is a magic process 
. The biggest problem is that I do not know how to normalized to the unit of kg−1 d−1. 
Would you please help me ? Any advice will be greatly appreciated
please give me some advices please!
Best wishes 
please help me. I am very stupid 