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Classifying near-range echoes detected by the mid-latitude SuperDARN radars Elizabeth McCubbin and Simon Shepherd Thayer School of Engineering, Dartmouth College, Hanover NH. Methods. Results. Introduction. Classifying Meteors Trail Echoes Maximum range gate: 5 Minimum power: 3 dB
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Classifying near-range echoes detected by the • mid-latitude SuperDARN radars Elizabeth McCubbin and Simon ShepherdThayer School of Engineering, Dartmouth College, Hanover NH Methods Results Introduction Classifying Meteors Trail Echoes • Maximum range gate: 5 • Minimum power: 3 dB • Maximum velocity: 150 m/s • Maximum vel. Error: 50 m/s • Minimum spectral width: 25 m/s Dartmouth College led the build of two additional radars with 24 beams near Christmas Valley, Oregon in November as part of the collaboration to develop a network of mid-latitude radars. Recent research on near-range backscattering drifts, has focused on how to determine the classification of meteors trail echoes from other backscattering, such as E-region irregularities and background noise, using the mid-latitude radars. With two radars in close proximity, a comparison on derived velocities show different results that may be caused from E-region plasma drifts that have similar characteristics of meteor trail echoes. A clear distinguish on classifying meteor trail echoes will be a useful tool to develop a global analysis of neutral winds with multiple SuperDARN radars around the mid-latitude region. 2011 01 20 (13:54 UT) Power Meteor scatter in the figures above peak around dawn (bold line is night), where an influx of meteors occur as the earth revolves around the sun [1]. Future Directions Classifying Neutral Winds • Minimum Beams: 5 • Minimum degree b/w first and last beam: 40 • Minimum meteors: 150 Process • Resolution: 6 minutes (3 scans) • Minimum weighted mean: 5 per beams • Minimum days: 10 (for month average) Meteors trails can be seen as “grainy near-range echoes” [2] typically within the first 5 range gates. Velocity References [1] Ceplecha , Zdenek, Jiri Morovicka, W. Graham Elford, Douglas O. Revelle, Robert L. Hawkes, Vladimir Porubcan, and Milos Simek. "Meteor Phenomena and Bodies." Space Science Reviews 84 (1998): 327-471 [2] Hall, G. E., J. W. MacDougall, D. R. Moorcroft, J.-P. St.-Maurice, A. H. Manson, and C. E. Meek. "Super Dual Auroral Radar Network Observations of Meteor Echoes." Journal of Geophysical Research 102.A7 (1997): 14603-4614 The Least Square Fit Model is applied with independent variables of line-of-sight velocity and the azimuthal angle to derive the zonal and meridonal velocity components. Above shows an example of E-region echoes within the meteor classification restrictions. Derive velocities may be directed towards plasma convection.