1. Observability of NEIALs with the Sondrestrom and Poker Flat incoherent scatter radars.
- Author
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Michell, R.G. and Samara, M.
- Subjects
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INCOHERENT scatter radar , *METEOROLOGICAL observations , *RADIO auroras , *ZENITH distance , *MAGNETIC fields , *ION acoustic waves , *WAVENUMBER - Abstract
Abstract: We present coordinated optical and radar observations using the Poker Flat Incoherent Scatter Radar (PFISR) in Alaska and the Sondrestrom radar in Greenland. Several cases were examined where intense, similar-looking dynamic auroral structures were observed in the magnetic zenith. The presence or absence of Naturally Enhanced Ion Acoustic Lines (NEIALs) was investigated in both sets of radar data. In all cases, the aurora exhibited small-scale ( โ1km), dynamic features that were observed with both all-sky and narrow-field of view (19°) imagers. In all of the cases examined, the PFISR radar observed NEIALs while the Sondrestrom radar did not, despite similar auroral morphology. The main difference between the radars, namely the probing wave number, provides strong evidence for a limiting spatial scale of between 10 and 15cm for the enhanced wave activity responsible for NEIALs. This has implications for constraining the models of NEIAL generation mechanisms. [Copyright &y& Elsevier]
- Published
- 2013
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