Simulating a reaction channel with two phi mesons decaying each in two muons after 9800 events GEANT4 (4.5.0_p01) crashes with the following exception: G4LENeutronInelastic: should be capture process! *** G4Exception: Aborting execution ***
Hi, this one turns out to be significantly harder than expected. I verified the cross-sections and the condition under which the exception occures in the final state generator. I find that this condition should indeed never occure for all elements I tested... What I would to progress from here are the values for the 4-momentum of the incident neutron, and the characteristics of the material, where the problem occures. Can you please run the program in the debugger, and break in G4Exception, to get at this information (or just put some printout in from of the exception in the source file - G4LENeutronInelastic.cc, blocks starting at lines 54, and 56)? Many greetings, Hans-Peter.
Archiving for the record..... This was a tough one. What you have there is a neutron with a 1meV (1 milli electron volt) kinetic energy. As it turns out, the inelastic cross-section for iron (the 56 isotope) is indeed non-zero down to the lowest energies. This is a extremely rare case, but all is correct. It is the exception that is misplaced. It occures in two places in the same file. I'll comment this in the next release. I would still be happy, if you could verify this in the debugger, and print for me the value of the 'theLastCrossSection' variable? This is a data member of the G4HadronInelasticProcess, that the process using G4LENeutronInelastic (G4NeutronInelasticProcess) derives from. It was put there for no other reason than for being able to check things in circumstances like these. Many greetings, Hans-Peter. Olaf Hartmann wrote: > > + Can you please run the program in the debugger, and break in > G4Exception, to get > + at this information (or just put some printout in from of the > exception in the > + source file - G4LENeutronInelastic.cc, blocks starting at lines 54, > and 56)? > > Hi Hans-Peter, > > it was tried with debug version of G4.5.0_p01, but under this > circumstances it never > came to the exception. So, the idea with the printout was checked, here > the result: > > 4-momentum (-0.000599026,-0.00142241,-0.000165049;939.566) > material Material: Iron density: 7.780 g/cm3 temperature: > 273.15 K pressure: 1.00 atm RadLength: 1.779 cm > ---> Element: Iron Z = 26.0 N = 55.8 A = 55.84 g/mole > fractionMass: 100.00 % Abundance 100.00 % > G4LENeutronInelastic: should be capture process! > > *** G4Exception: Aborting execution *** > > Cheers, > Olaf.
