OH(6-2) SPECTRA AND ROTATIONAL TEMPERATURE-MEASUREMENTS AT DAVIS, ANTARCTICA

The OH(6-2) band was monitored during 1990 at Davis, Antarctica (68.6 degrees S, 78.0 degrees E) using a Czerny-Turner scanning spectrometer . Spectra obtained with a 0.15-nm bandwidth and wavelength steps of 0. 005 nm have been recorded in an attempt to isolate auroral features. T his has enabled detailed study of weak features in the region lambda 8 37.5-855.5 nm. These weak features can contribute to the apparent inte nsity of P-branch lines and to the background. Their presence is allow ed for in our calculation of rotational temperature, but the P-1(3) li ne is excluded because of significant contamination. An average temper ature of 221 +/- 2 K is obtained from a selected data set of 104 spect ra. The mid-winter average temperature, for the months of May, June an d July, is 224 +/- 2 K, which is consistent with the 1986 CIRA model v alues for mid-winter at this height and latitude, but this result is d ependent on the choice of transition probabilities. Preliminary assess ments of seasonal and diurnal variations in rotational temperature and intensity are presented.