A nitrogen ion laser pumped by a rapid discharge

The pumping mechanism of the N 2 + ion laser excited by a rapid discharge in a He-N 2 mixture has been examined experimentally. The dependence of the laser output on temperature and pressure of gas mixture and the time history of the gain of active medium are measured, leading to the conclusion that the electron impact excitation of the Na 2 + (B 2 Sigma u + ) state is the dominant excitation process in the case of high speed excitation.