Absorption of H and D Ly-α radiation by O2 molecules at high temperatures

Absorption cross sections of molecular oxygen were measured at the H and D Ly-α wavelengths (1215.67 and 1215.34 Å) between 800 and 1700°K, the cross sections being given by the equation σ (cm²) = 4.2E-18 exp(-3070/T) (4.2E-18 = 4.2 × 10^-18). The absorption cross section for v = 1 is (9±2)E-19 cm² and that for v = 2 is (7±3)E-18 cm², compared to 1.E-20 cm² for v = 0. Vibrational relaxation times were found to be in agreement with literature data over the range of common temperatures.