Intracavity spectroscopy utilizing lasers based on $F_2^-$ color centers in LiF crystals

A description is given of an intracavity spectroscopic system based on a laser utilizing $F_2^-$ color centers in a crystal of LiF and operating in the free-running regime emitting at wavelengths in the range 1.1–1.25 $\mu$. The color-center laser was pumped by a neodymium laser. The absorption spectra of water vapor, methane, and ammonia were recorded.