Population inversion of transitions in neon-like ions

It is shown that a population inversion occurs for three types of transition in neon-like ions with Z~7–15 in a steady-state plasma. A steady-state gain of ~100 cm–1 may be expected for the 2p53p1S0→2p53S1P1 transition in the wavelength range λ~40–80nm. Radiation trapping by the 2p6→2p53S and 2p6→2p53d transitions alters drastically the gain.