Correction to the dissociation rate in an open-cycle FAF CO2 laser amplifier.

Abstract

On the basis of the transient mass-spectrum analysis of CO2 gas dissociation for various input probe powers Pin, plasm alengths l, gas-flow velocities v and discharge currents Idis, the dissociation rate (1-δ) and dissociation factor ξ of a CO2 molecule are found to be modified in an open-cycle fast-axial flow (FAF) CO2 laser amplifier. The effective dissociation constant Deff related to (1-δ) is found to be corrected as a function of v and input probe irradiance Iin, and the dissociation-rate constant ad concerned with the dissociation factor ξ is found to be modified to be v-dependent, though these have been regarded as a constant in a sealed-off system. Furthermore, suction rate δf due to the difference in the evacuation rate between CO2 and CO or O2 is found to be taken into consideration in (1-δ). Corrections for Deff and αd are also qualitatively discussed. By using these corrected parameters, the small-signal gain γ0 is calibrated to explain experimental results satisfactorily.