if you have a device similar to a stun gun, with a spark continuously jumping across the 2 contact points. electric field has to rip electrons from the air moecules leaving positive ions - creating plasma. now imagine you have a negatively charged disc nearby the device which is covered in a highly insulating material. is it practically possible to give the disc enough charge so that as the electrons are ripped from the air atoms, the disc attracts and collects the positive ions and repels the electrons and holds the positive ions not letting them escape? since the disc has a protective insulating cover, the charge cannot escape or neutralize with the positve ions so it would just hold them there. can this be done? how could you figure out how much charge the disc would need? would the maximum volume of these positive ions be significant at all compared to the size of the disc?