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 C 5+ -is optically thick at the surface of a laser-irradiated carbon target. Optical depths of the order of 10 4 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.