Population inversion in laser-produced plasmas by pumping with opacity-broadened lines

It has been noted that line radiation-for example, the first member of the Lyman series of C5+-is optically thick at the surface of a laser-irradiated carbon target. Optical depths of the order of 104 can be anticipated with appropriate focusing geometry. Using such an optically thick and broadened line source it is calculated that population inversion and a measurable super-radiant gain can be achieved by resonance pumping in neighbouring ion species.