I Protons by ZnS:Ag

Hi

I need to know if a thin mylar film with deposited ZnS:Ag is capable to detect low energy protons, say 10 keV, emitted in a high vacuum.

 

gleem, websterling,
Thanks to you both.
A friend of mine is building a Cockroft-Walton accelerator, now at the ion source stage.
The ion source is delivering 1mA of ions, and 4 inches below the extraction electrode he placed a thin mylar covered with ZnS:Ag.
It fluoresces strongly and the invisible beam can be displaced with a strong magnet.
So, there are ions and fluorescence, under 10 kV.
The system has some leaks, so it is not fed only with H2, there is some air also. At first I guessed was UV-induced fluorescence but the magnet move the beam.
See the attached image. At the center of the electrode there is a small piece of the mylar as well a "collar" outside it.