I use GEANT4.7.0 without patch to simulation antiproton annihilation with gold and reconstruct the trajectory of charged measons. I use the physics list from the copy of novice exampleN04. During running of the programme, a warning message issued by GEANT as follows: >>> Current event ID is 2900; 146 trajectories stored in this event. >>> Current event ID is 3000; 108 trajectories stored in this event. G4HadronicProcess: track in unusable state - 1 G4HadronicProcess: returning unchanged track *** G4Exception : 001 issued by : G4HadronicProcess bailing out *** This is just a warning message. >>> Current event ID is 3100; 3 trajectories stored in this event.
I will try to reproduce your problem. Please send a tar file of your code to me: dwright@slac.stanford.edu I will compile it against Geant4 7.0 and go from there.
Hi, this one was assigned incorrectly.
Hi, this is a feature, rather than a bug. What happens is this: A low energy charged particle is being tracked. Based on the inelastic cross-section, hadronics decides that the particle should undergo an inelastic interation, and limits the step. Due to fluctuations the particle comes to a rest before reaching the designated locus of the interaction. At rest, the inelastic process can of course not handle secondary production. It bails out. The warning is there only, because if this is a frequent condition, then the stepping approximation is not good for your problem, and you will want to use user-defined step limits to make smaller steps by hand. Note also that I have never seen such a case to date. Many greetings, Hans-Peter.
