開放循環型FAF CO₂レーザー増幅器におけるガス解離の補正

抄録

On the basis of the transient mass-spectrum analysis of CO₂ gas dissociation for various input probe powers P_in, plasm alengths l, gas-flow velocities v and discharge currents I_dis, 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 D_eff related to (1-δ) is found to be corrected as a function of v and input probe irradiance I_in, and the dissociation-rate constant a_d 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 δ_f 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 D_eff and α_d are also qualitatively discussed. By using these corrected parameters, the small-signal gain γ₀ is calibrated to explain experimental results satisfactorily.