Cherenkov with C2F6 gas radiator

Dear all
I’m trying to create a simulation in which I detect Cherenkov gammas coming from
protons with pt = 10 GeV entering a volume of C2F6 (refraction index = 1.0008).
Unfortunately it seems that the particle passes the volume without caring so much in creating
the Cherenkov light (but it does if I put an aerogel box).
The end result should give me two cones, one from the aerogel and one from the gas radiator.
Do you have any ideas? I haven’t seen gas radiators around with GEANT4.

_Geant4 Version:11.2.1
_Operating System:Ubuntu 22.04
_CMake Version:3.25.1


Welcome to the Geant4 forum!

In general, when things do not work as expected, I found useful to run the simulation with a visual interface (such as the Qt option) to visualize any anomaly of generation or tracking with your own eyes. In addition, you may want to enable tracking verbosity with /tracking/verbosity 2. These tips are explained in the beginner Geant4 course, here you may find the material, and the videos are in the CERN CDS.

Could you post the optical properties of the gas radiator, and a screenshot of the graphical visualization of an event where the gas and the 10 GeV proton are shown?