20Neon isotope problem

Hi all,

I am getting very different results from the same experiment on different geant4 versions.

On version 11.2.2, decaying 238U in pure oxygen would produce neon (alpha reacts with oxygen nuclei)

e.g.

Ne20: 108 Emean = 1.099 MeV ( 700.7 keV → 1.633 MeV) stable

On version 11.3, the same experiment yields no neon.

The example above was QGSP_BIC_HP_EMZ, but it seems to happen regardless of physics list.

What is causing the difference? Is this an error?

Thanks in advance.