Self-modulation lasing regimes in a fast-flow СО$_2$ laser

Numerical simulation of self-modulation lasing regimes has been carried out for a СО$_2$ laser with transverse flow of the active medium through an unstable resonator with inhomogeneous internal pumping. Two types of steady-state self-modulation oscillation differing in the feedback mechanism were observed. The type of lasing regime and the conditions of its realization depend both upon the pumping profile and upon the composition and pressure of the working mixture, which makes it generally possible to control temporal characteristics of lasing.