New laser transitions in the spectrum of tin and population inversion mechanism

A stimulated emission of the 558.9, 579.9, 1062, and 1074 nm lines in the spectrum of Sn II and of the 657.9 nm line in the spectrum of Sn I was achieved. The ion laser transitions were pumped by the recombination of Sn²⁺ and by the charge exchange in collisions of helium or neon ions with tin atoms.