Photochemical rates in the equatorialF₂region from the 1958 eclipse

The F2-region electron-density data from the eclipse on October 12, 1958, at Danger Islands has been analyzed with a new method. It is shown that (1) temperature changes and transport of electrons were probably negligible during the eclipse, and (2) the rate of photoionization q(h) and the linear recombination coefficient (‘attachment coefficient’) β(h) can be approximated between 290 km and 400 km by where the height h is measured in kilometers. The rate of formation of ion pairs between 290 and 400 km is (.76)1010 ion pairs/cm2 sec, or about (0.25) ergs/cm2 sec. This implies a total rate of energy absorption in the F region of at least 2 ergs/cm2 sec.