{HEAD ~ Broadband photo pumping} of {TAIL ~ ions}, as from a flash lamp or other broadband source of photons, to create 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 
{ HEAD ~ Broadband photo pumping } of { TAIL ~ ions } , as from a flash lamp or other broadband source of photons , to create 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
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL 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 OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH