Electron trajectories at low energy in a low electric field

[cghw02]

OK, I found the solution here:

How to track a positron below 100 eV?

Recently I’m trying to track the positrons using the standard EM physics. However, it is strange for me to find that the 100-eV positrons travelling in a Laboratory vaccum would lose all their energy because of processes named “Transportation” and “eIoni” within a single step. This seems to be related to the low energy cut of the G4eIonization process, but I currently have no idea how to change it. Moreover, I’m interested in tracking positrons with energy below 0.025 eV, is it feasible using t…

I need to add the following command:
/process/em/lowestElectronEnergy 0.0 eV

and then things seem to work.

Best Wishes
Chris