Fluorescence emission of {TAIL ~ iron} or cerium in glass is excited and imaged onto {HEAD ~ segmented detectors} 
Fluorescence emission of { TAIL ~ iron } or cerium in glass is excited and imaged onto { HEAD ~ segmented detectors }
OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD