Problem 2356

Summary:	Missing unit in G4AtomicShells::GetNumberOfFreeElectrons
Product:	Geant4	Reporter:	Valentin <niess>
Component:	materials	Assignee:	Vladimir.Ivantchenko
Status:	RESOLVED FIXED
Severity:	minor
Priority:	P4
Version:	10.7
Hardware:	All
OS:	All

Description Valentin 2021-04-07 13:37:00 CEST

In method ComputeDerivedQuantities of G4Material.cc, at line:

https://gitlab.cern.ch/geant4/geant4/-/blob/master/source/materials/src/G4Material.cc#L318

G4AtomicShells::GetNumberOfFreeElectrons is called with a threshold elecTh given as `15 * CLHEP::eV` i.e. 15E-06 (MeV). However, in the corresponding method at line:

https://gitlab.cern.ch/geant4/geant4/-/blob/master/source/materials/src/G4AtomicShells.cc#L792

elecTh (th) is compared to fBindingEnergies which is expressed raw in eV, e.g. 13.6 for H. As a result the comparison always fails. Instead, the previous line should be:

if (fBindingEnergies[i] * CLEHP::eV <= th) ...

E.g. as here:

https://gitlab.cern.ch/geant4/geant4/-/blob/master/source/materials/src/G4AtomicShells.cc#L763

Comment 1 Vladimir.Ivantchenko 2021-04-19 09:02:29 CEST

Hello,

thank you very much for this very detailed and clear bug report. The fix is merged to the current master of Geant4 and prepared for the next patch for Geant4 10.7. The date of this patch is not yet defined.

Vladimir