Absorption cross-sections in the vacuum ultra-violet. - I. Continuous absorption of oxygen (1800 to 1300 Å)

Absorption cross-sections for oxygen in the region 1670 to 1360 Å, corresponding to the process O23Ʃg- + hv → O(3P) + O(1D), have been measured. The cross-section has a maximum value of 1⋅81 x 10-17 cm2 at 1450 Å and falls to half-value at 1567 and 1370 Å. The paper includes an account of technical methods of quantitative absorption spectrophotometry in this part of the vacuum ultra- violet.