Broadband photo pumping of {HEAD ~ ions}, as from a flash lamp or other broadband source of photons, to create {TAIL ~ a population inversion} is highly inefficient because only a small fraction of the energy emanates within the very narrow range of wavelengths near the resonant absorption frequency of the transition 
Broadband photo pumping of { HEAD ~ ions } , as from a flash lamp or other broadband source of photons , to create { TAIL ~ a population inversion } is highly inefficient because only a small fraction of the energy emanates within the very narrow range of wavelengths near the resonant absorption frequency of the transition
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL 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