an anode with {TAIL ~ positive electric potential}; anode is located close to {HEAD ~ a gas distributing system}, and it is placed in a discharge channel external wall between two cylindrical external dielectric walls 
an anode with { TAIL ~ positive electric potential } ; anode is located close to { HEAD ~ a gas distributing system } , and it is placed in a discharge channel external wall between two cylindrical external dielectric walls
OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH