ABSTRACT
Some basic aspects of discharge physics and the collision processes relevant to gas-laser systems which operate in low-pressure discharges are discussed. Specific topics include: the constraints which determine steady-state plasma parameters; collisional excitation and de-excitation and the approach to equilibrium; factors underlying scaling laws and power limitations of the He–Ne, He–Cd and Ar ion systems; charge transfer excited metal ion lasers; the negative glow lasers; and pulsed metal-vapour systems such as the copper-vapour laser.
