Interferometric studies of the twilight and nightglow sodium D-line profiles

摘要: Abstract A 150 mm aperture, pressure scanned Fabry-Perot interferometer has been used to study the midlatitude twilight and nightglow sodium D-line profiles. The line width measurements during evening morning indicate that layer temperature rises a midwinter maximum (∼230 K) then falls midsummer minimum (∼150 K), in qualitative agreement with CIRA 1972 model predictions. Nightglow intensity obtained highly variable behaviour, ranging from near-constant intensities, monotonically falling, rising falling intensities night. Broadening of profiles yields atom dissociation kinetic energy (46 ± 4) meV. This suggests Chapman NaO + O chemiexcitation process, rather than dissociative recombination “corkscrewing” ions electrons, gives rise nightglow.