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Auroral Turbulence I (A.T. I)
Launch date: 6 March, 1994
Launch time: 08:21 UT
Participating institutions: Torbert (UNH); Kelley (Cornell); LaBelle, Lund, Trimpi, Gewirtz (Dartmouth); Danish Meteorological Institute [DMI]
Vehicle apogee: 440km
Location: Poker Flat, AK (65.13¡ N, 147.48¡ W)
Instrument list: ons/Electrons (UNH), Electric Field (Cornell), Plasma Frequency Tracker (Dartmouth), Faraday Ring Ammeter (UNH/DMI)
On Auroral Turbulence I, Dartmouth provided a plasma frequency tracker and also
contributed to the electric field experiment.
In the electric field data, electromagnetic ion cyclotron waves were observed in both electric and magnetic field waveforms during an auroral arc crossing, and the cyclotron waveform was correlated one-to-one with modulations in the field aligned electrons at the same frequency, about 10 Hz. Previous studies observed a general correlation between wave modulations and particle modulations, but this was the first time that the modulations themselves were correlated. Making some assumptions about the electron density as a function of height, the time delay between the waves and particles suggested a source height of 5000 km consistent with where the modulation frequency would match the local cyclotron frequency. Later observations with the FAST satellite explored this phenomenon in greater detail, observing similar correlations between waves and particles but with better signal to noise ratio. For details, see Lund et al., 1995, and Lund and LaBelle, 1997.
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51. Lund, E.J., J. LaBelle, M.C. Kelley, R.B. Torbert, W. Peria, K. Liou, F. Primdahl, C.A. Kletzing, H.C. Stenbaek-Nielsen, A. Ranta, G. Haerendel, and H. Frey, Observation of electromagnetic oxygen cyclotron waves in a flickering aurora, Geophys. Res. Lett., 22, 2465, 1995.
62. Lund, E.J., and J. LaBelle, On the generation and propagation of auroral electromagnetic ion cyclotron waves, J. Geophys. Res., 102, 17241, 1997.
Lund, E.J., M.L. Trimpi, E.H. Gewirtz, R.H. Cook, and J. LaBelle, The plasma frequency tracker: an instrument for probing the frequency structure of narrow band MF/HF electric fields, to appear in Proc. Chapman Conf. on Measurement Techniques, 1997.
Note: Numbers refer to Full Publication List
Also Note: Most abstracts are freely available through NASA's Astrophysics Data System Bibliographic Services (ADS). Some are available locally. Full texts are only available to users within institutions that subscribe to the corresponding web-based journal.