An Investigation of the Ionospheric D Region at Sunrise: 2, Estimation of Some Photodetachment Rates


  • R. P. Turco,

  • C. F. Sechrist Jr.


The photodetachment rates of several negative ions believed to be present in the D region are estimated for sunrise conditions. The photodetachment cross sections of O and O2 which have been measured in the visible and infrared wavelength ranges are used. Since the photodetachment cross sections of NO2 and NO3 are not yet known, the behavior of their rates could only be estimated. Infrared band absorption by H2O and CO2 is included in the calculations. For atoms and molecules with large electron affinities the ozone ultraviolet absorption is important. The effects of photodetachment on D-region behavior are discussed and found to be relatively unimportant.