gas laser

A laser in which the active medium is a gas containing a laseractive species. It is typically composed of a plasma discharge tube containing a gas that can be excited with an electric discharge.
Source:
PAC, 1995, 67, 1913 (Nomenclature, symbols, units, and their usage in spectrochemical analysis-XV. Laser-based molecular spectroscopy for chemical analysis - laser fundamentals (IUPAC Recommendations 1995)) on page 1919
See also:
PAC, 1996, 68, 2223 (Glossary of terms used in photochemistry (IUPAC Recommendations 1996)) on page 2244