Abstract

MELO, S. M. Ludovico; CLEMESHA, B. R.  and  TAKAHASHI, H.. Oxygen Excited States in the Mesosphere. Rev. Bras. Geof. [online]. 1997, vol.15, n.1, pp. 45-58. ISSN 0102-261X.  http://dx.doi.org/10.1590/S0102-261X1997000100005.

Simultaneous measurements of the nightglow profiles of the O₂ Herzberg I bands, the O₂ atmospheric (0-0) band and the OI 557.7 nm line are discussed in terms of the excitation and loss of the O(¹S), O₂(b¹S_g⁺ ) and O₂(A³S_u⁺ ) states. The measurements were carried out by rocket-borne photometers launched from Alcântara (2⁰S, 44⁰W) on May 31, 1992 at 23:52 LT. The rocket payload contained 6 longitudinal photometers to measure the OI 557,7 nm and NaD 589 nm lines, the O₂ atmospheric (0-0) and Herzberg I bands and the continuum at 578 nm, together with 4 transverse photometers measuring the OI 630 nm and NaD 589 nm lines, the OH(8-3) band and the continuum at 710 nm. The results for the O(¹S) and O₂(b¹S_g⁺ ) states suggest the validity for the equatorial region of empirical parameters derived from measurements made at high latitudes. For the O₂(A³S_u⁺ ) states, the quenching rates required to explain the measurements are higher than the values derived from previous airglow measurements but in agreement with recent laboratory measurements.

Keywords : Aeronomy; Airglow; Atmospheric spectroscopy.