Bug found in 10.1 by Luciano Pandola, but most probably already there in g4.9* version. Bug description: ---------------- +The deexcitation of 99Tc[142.68] is not well reproduced, and in general gamma deexcitation between nuclear levels separated by energy<10 keV, will not occur. +For 99Tc[142.68] The following de-excitation is expected: 99Tc[142.68]->99Tc[140.51]->99Tc with 89 % production of 140.51 keV line, and the rest mostly in production of electron conversion +The following output is obtained from Geant4 simulation: 99Tc[142.68]->99Tc with mostly electron conversion produced, and direct de-excitation to the ground. The 140.51 level is missed! Proposed Bug fixing: ----------- +The problematic code is G4DiscreteGammaTransition.cc. The tolerance in line 79 is much too high (10keV): static const G4double tolerance = 10*CLHEP::keV; This high tolerance has the effect in line 155 if (gammaEnergy < tolerance) { gammaEnergy = excitation; } to forbid the decay between levels separated by less than 10 keV. Proposed solution: The tolerance should be set much lower and the treatment of very low energy gamma should be reviewed later on. We propose as a first fix to change line 79 by: static const G4double tolerance = 0.1*CLHEP::keV; Best regards Laurent
Hello, There is a tag for the de-excitation sub-library which recently was accepted. In this tag all energy "tolerances" are set to 0.1 keV. Please, check that the problem 99Tc is resolved. The trunk of de-excitation may be used. Vladimir
I confirm that the 99Tc[140.51] level now appears with the change to 0.1 keV tolerance.
