{HEAD ~ Ions} are trapped in a potential well in the linear trap 30 and are bunched at {TAIL ~ the bottom} of the potential well adjacent an exit segment 50 
are bunched at
{ HEAD ~ Ions } are trapped in a potential well in the linear trap 30 and are bunched at { TAIL ~ the bottom } of the potential well adjacent an exit segment 50
HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH