{HEAD ~ This invention} relates to apparatus for detecting charged particles and in particular to {TAIL ~ apparatus} for detecting charged particles in a gaseous environment 
relates particular to
{ HEAD ~ This invention } relates to apparatus for detecting charged particles and in particular to { TAIL ~ apparatus } for detecting charged particles in a gaseous environment
HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH OTH OTH OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH