An accelerating electrode field is set up in {TAIL ~ the chamber} by one or more electrodes, and {HEAD ~ the chamber} is sealed by an electronically conductive barrier so as to prevent gas leaking into the chamber, whilst being sufficiently thin to enable charged particles to travel across the barrier and thereby be detected by the detector 
An accelerating electrode field is set up in { TAIL ~ the chamber } by one or more electrodes , and { HEAD ~ the chamber } is sealed by an electronically conductive barrier so as to prevent gas leaking into the chamber , whilst being sufficiently thin to enable charged particles to travel across the barrier and thereby be detected by the detector
OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH