HR: 1340h
AN: SA23A-0307    [Abstracts]
TI: Interlaced Limb Scanning for Tomography
AU: * Budzien, S A
EM: budzien@nrl.navy.mil
AF: Naval Research Laboratory, Code 7623, Washington, DC 20375-5352 United States
AB: The Naval Research Laboratory has developed and flown far-ultraviolet limb scanners for characterizing thermospheric composition, densities, and temperature and ionospheric electron density. Each sensor collects measurements in the orbital plane, and the numerous intersecting lines-of-sight oversample the region and provide the capability to perform tomographic retrievals. However, these sensors were not originally designed for tomography so their operating mode is not optimized for 2-D retrievals. Under normal operations each instrument collects 90-sample limb scans over altitudes 75--750~km at a 90-second cadence, which provides good vertical resolution (down to 6 km) but limited horizontal resolution (5.6 degrees in latitude). For example, the 5.6-degree resolution limits the accuracy with which sharp gradients - --such as those associated with the Appleton anomalies - --can be retrieved. By utilizing an interlaced scan pattern, the same 90 lines-of-sight are sampled in a different order to improve horizonal resolution by a factor of 2--3 while retaining the nearly the same vertical resolution over each 90-sec period. Scan strategies, signal-to-noise concerns, spatial resolution, and retrieval accuracy considerations are presented.
DE: 0310 Airglow and aurora
DE: 0394 Instruments and techniques
DE: 2494 Instruments and techniques
SC: SPA-Aeronomy [SA]
MN: Fall Meeting 2005