Extracting nucleus-nucleus cross sections for proton therapy

Physics Processes, Models and Cross Sections
1

Dear Geant4 forum,

In an attempt to benchmark an in-house dose calculation algorithm against the Geant4 one I realized that I need to extract from Geant4 the nucleus-nucleus cross sections for a proton beam of <250 MeV.

Since I’m not knowledgeable enough to write my own code, I’ve tried using the xscompare tool. However, when I try and input the hadrons in flight processes I get a list of zeros.

Looking at the source code (in the PhysicsList.cc file located in the src directory) I see that the code uses the method ComputeCrossSectionPerVolume (line 231). According to the Application Developers Book (and also to line 227 of the same file I mentioned above) this method is part of the G4EmCalculator class.

  1. Is it correct to conclude that this method is then unsuitable for the extraction of the hadronic processes cross sections?

In an attempt to find out how to modify this tool for my purpose I found out about the GetCrossSection method which could be applied to the G4TENDL dataset.

  1. Is it correct to conclude that this is the way to adapt the tool in order to extract the nucleus-nucleus cross sections?

Any suggestions towards making use of this tool for my purpose are greatly appreciated.

Tiberiu

2

Hello,

G4EmCalculator is applicable only to EM processes, nothing to do with neutrons.

For total hadronic cross sections see $G4INSTALL/example/extended/hadronic/Hadr00

VI

3

Hello,

Thank you for the answer. I extracted the necessary data.

I have a new question. Is it possible to extract the absorption cross section data for a proton beam as a function of the process? For example, I would like to extract the cross section for the (p, 2p′), (p, 2p′n), and (p, alpha) processes. I could not find the option in the G4HadronicProcessStore class reference.