Problem 837

Summary: About Gamma-ray generated by nuclear reaction
Product: Geant4 Reporter: fengyx
Component: processes/hadronic/cross_sectionsAssignee: dennis.herbert.wright
Status: RESOLVED FIXED    
Severity: normal    
Priority: P2    
Version: 7.1   
Hardware: PC   
OS: Linux   

Description fengyx 2006-02-06 12:08:59 CET 
Dear Sir,

I am trying to use GEANT4 to simulate the Gamma-ray produced via nuclear
reactions induced by ~50 MeV proton, such as p + C12 etc. I found some
cross-sections for this kind of reactions from Dyer's paper (Phys. ReV. C. 1981,
Vol. 23, p. 1865). I am not sure wether current GEANT4 (such as 7.1 or 8.0) has
token that into account or not.

Could you let me know wether GEANT4 includes this kinds of reaction or not?
If not, could I add those cross sections in a simulation with GEANT4?

Thanks


-- FENG,YUXIN
Comment 1 dennis.herbert.wright 2006-03-13 17:50:59 CET 
Geant4 does have some discrete gamma levels, but I'm not sure that all those
seen in the Dyer paper are included.   Please try simulating p + 12C
using the Precompound model, and remember to

setenv G4LEVELGAMMADATA

to the location of the file PhotonEvaporation2.0 which you can download from
the Geant4 webpage.

If the lines are not there, then you will have to make your own (p,gamma) cross
section class.   This can be done by deriving from G4VCrossSectionDataSet.hh,
implementing the IsApplicable and GetCrossSection methods, and then assigning
it to the proton process with the AddDataSet method.   Examples of such
specialized cross section sets are found in
geant4/source/processes/hadronic/cross_sections