Time biasing problem with Cf252 source

Dear Geant4 Users,

I am trying to track the secondary particles generated from Cf-252 fission events in my simulation.

To save simulation time, I attempted to use the time biasing technique to simulate the activity.

I used the example files from the rdecay01 and NeutronSource directories. However, after modifying the timewindowbiasing.data file to create a window between 0 and 1 second (and other time windows in different trials), I noticed that the spontaneous fission events from the Cf-252 source (which generate neutrons) were not simulated. Only alpha decay events were simulated.

I am wondering if the time biasing technique is only compatible with alpha decay events.

Are there any other methods to simulate a high-activity source effectively?

Sincerely,

Geant4 Version: 11.2.2
Operating System: Windows 11
Compiler/Version: Visual Studio 2022
CMake Version: 3.28.0