I agree. The documentation essentially states as much:
“The results concerning the production of γ-rays have to be questioned always. For example, the information on the number and energies of γ-rays emitted in the neutron capture process is incomplete for almost all the nuclei and is frequently also uncorrelated. When the information is available, it will be used, but one can obtain results which are quite far from reality on an event by event basis: the total energy of the cascade won’t be correct in many cases and only some specific γ-rays which are stored in the neutron databases will be emitted. If there isn’t any information concerning these γ-rays, Geant4 will use a simple a model instead which is generally missing the relevant spectroscopic information.”
My approach to neutron capture processes now is to check each isotope I will use against the NNDC data base, using Hadr03, before I put it in a simulation of my own. It is tedious because you have to check it for several ParticleHP parameter settings and possibly different versions of Geant4 for each each isotope. If anyone has a better method, I would be delighted to hear it.
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