Hi everyone,
I have been running a simulation (based on simulation B1) and encountered some issues with the scintillation behaviour.
My computer set-up is macOS Monterey, version 12.4, M1 chip. Geant4 has been re-installed, but it didn’t seem to help. I am currently using Geant4 version 11.0.3
The simulation runs fine if a line registering the Optical Physics registration in the Physics list is commenting out.
Has anyone encountered this issue previously or know how to fix it?
The error message is the following:
G4WT4 > → Event 0 starts with initial seeds (13049039,61775110).
G4WT4 > G4VParticleChange::CheckIt : the true step length is negative !! Difference: 0.0387463[MeV]
G4WT4 > opticalphoton E=3.34861e-06 pos=-0.000520943, 0.00242823, -0.191418
G4WT4 > -----------------------------------------------
G4WT4 > G4ParticleChange Information
G4WT4 > -----------------------------------------------
G4WT4 > # of secondaries : 0
G4WT4 > -----------------------------------------------
G4WT4 > Energy Deposit (MeV): 0
G4WT4 > Non-ionizing Energy Deposit (MeV): 0
G4WT4 > Track Status : StopAndKill
G4WT4 > True Path Length (mm) : -0.0387
G4WT4 > Stepping Control : 0
G4WT4 > First step in volume
G4WT4 > Mass (GeV) : 0
G4WT4 > Charge (eplus) : 0
G4WT4 > MagneticMoment : 0
G4WT4 > = : 0*[e hbar]/[2 m]
G4WT4 > Position - x (mm) : -0.521
G4WT4 > Position - y (mm) : 2.43
G4WT4 > Position - z (mm) : -191
G4WT4 > Time (ns) : -0.000178
G4WT4 > Proper Time (ns) : 0
G4WT4 > Momentum Direct - x : -0.243
G4WT4 > Momentum Direct - y : 0.113
G4WT4 > Momentum Direct - z : -0.963
G4WT4 > Kinetic Energy (MeV): 3.35e-06
G4WT4 > Velocity (/c) : 0.725
G4WT4 > Polarization - x : -0.634
G4WT4 > Polarization - y : 0.733
G4WT4 > Polarization - z : 0.246
G4WT4 >
-------- EEEE ------- G4Exception-START -------- EEEE -------
*** G4Exception : TRACK001
issued by : G4VParticleChange::CheckIt()
Step length and/or energy deposit was illegal
*** Event Must Be Aborted ***
G4WT4 > G4Track (0x142653ea8) - track ID = 2, parent ID = 1
G4WT4 > Particle type : opticalphoton - creator process : Scintillation, creator model : Undefined
G4WT4 > Kinetic energy : 3.34861 eV - Momentum direction : (-0.242935,0.113321,-0.963401)
G4WT4 > Step length : -38.7463 um - total energy deposit : 0 eV
G4WT4 > Pre-step point : (-0.530356,2.43262,-191.455) - Physical volume : Sheet (Scintillator)
G4WT4 > - defined by : not available
G4WT4 > Post-step point : (-0.520943,2.42823,-191.418) - Physical volume : Sheet (Scintillator)
G4WT4 > - defined by : OpWLS - step status : 4
G4WT4 > *** Note: Step information might not be properly updated.
G4WT4 >
-------- EEEE -------- G4Exception-END --------- EEEE -------