Absorption of carbon dioxide laser lines in OsO4 vapor

The absorption spectra of OsO₄ vapor were determined within the limits of the Doppler widths of the CO₂ laser lines emitted due to the transitions in the Р and R branches of the vibration-rotational band 00⁰–10⁰0. A study of the absorption saturation effect was made. The absorption coefficients were obtained for the principal and "hot" transitions (α₀ + β₀ = 0.074 cm^–1·torr^–1). The intensity corresponding to the absorption saturation (I_s = 0.8 W·cm^–1·torr^–1) and the absorption coefficient corresponding to the "hot" transition bands (γ = 5) were also determined. These parameters were the characteristics of the saturation interpreted on the basis of a four-level absorber model. The vibrational relaxation time (τ₀ = 3.8 msec/torr) of OsO₄ was calculated.