In 2001, we are planning to install a bare CCD camera detector that is expected to improve the sensitivity of these measurements by a factor of 15. After testing the new CCD detector in 630 nm measurements, the observations will be extended to determinations of 731.615 nm OH winds and temperatures at the centroid altitude of 87 km. Calibration measurements at 632.8 nm are taken with a stabilized He-Ne laser every 5 to 10 minutes throughout the night. To compensate for this we subtract from each zenith line position the line position of the 632.8 nm interpolated to the zenith measurement time to obtain an offset value. The average of these values for the whole night is the reference offset between the 632.8 nm laser line and the nightglow 630.0 nm line position for zero velocity.
Bins are every half hour, where the time given is the midpoint of the bin.
The errors reported for the monthly means are not measurement error bars, but are the standard error of the mean monthly values, which are generally much larger than the measurement error bars. The plots are labelled January through December, where each month is 24 hours in local time and the midpoint of the month is local midnight for the monthly average. Measurements and plots between 1996 and 1999 are nightly observations of the horizontal winds, the vertical winds, the neutral temperatures, and the real emission rates in Rayleighs. The south direction was chosen in addition to the zenith to plot the temperature and emission. The intensity values to the south of Arequipa are significantly higher because the Observatory is looking toward the Appleton anomaly, where the ionosphere has higher electron density due to the fountain effect - the uplifting of plasma from the magnetic equatorial region.