Since beam 142 is collimated, {HEAD ~ the ideal form} for {TAIL ~ the injected beam} is also collimated 
for
Since beam 142 is collimated , { HEAD ~ the ideal form } for { TAIL ~ the injected beam } is also collimated
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH