I am sorry that I am not exactly sure which category this should be in.
I am modeling a fast neutron spectrometer using Geant4 10.6.1. It is an ionization chamber which consists of a cylinder containing high pressure He3 and Ar. It is illuminated with monochromatic neutrons (25meV [thermal], 500keV, 1000keV, 1500keV, 2000keV, 2500 keV) uniformly across the face either at 0 or 90 degrees to the symmetry axis. The spectrometer sits in air. I then calculate total energy deposited in the volume per event and output the results. The resulting spectra look good.
However, I am occasionally getting the following warning message. The rate of occurrence is about 0 to 3 per 10^8 events.
-------- WWWW ------- G4Exception-START -------- WWWW -------
*** G4Exception : hadEla001
issued by : G4HadronElastic::ApplyYourself
hElasticCHIPS wrong sampling t= 11275.2 tmax= 9953.46 for proton ekin=2.35936 MeV off (Z,A)=(2,3) - will be resampled
*** This is just a warning message. ***
-------- WWWW -------- G4Exception-END --------- WWWW -------
The ekin, t and tmax values vary from warning to warning. I can find no documentation on it.
In some of the simulations, I have surrounded the cylinder with a thin cylindrical shield of boron nitride and cadmium to suppress thermal neutrons. Again resulting spectra look good. However, 4 of the 7 runs output the following warning message just before the end of run (run is ended successfully, however).:
" Loop-counter exceeded the threshold value at 378th line of /path-to/geant4/geant4.10.06.p01/source/processes/hadronic/models/particle_hp/src/G4ParticleHPInelasticCompFS.cc. "
I looked in the Geant4 source and found the line of code, but I do not understand what is going on there.
Has anybody come across either of these messages and know what they mean?