Waveform and packet structure of lion roars

@article{Baumjohann1999WaveformAP,
  title={Waveform and packet structure of lion roars},
  author={Wolfgang Baumjohann and Rudolf A. Treumann and E. Georgescu and Gerhard Haerendel and K. H. Fornacon and Uli Auster},
  journal={Annales Geophysicae},
  year={1999},
  volume={17},
  pages={1528-1534}
}
The Equator-S magnetometer is very sensitive and has a sampling rate of normally 128 Hz. The high sampling rate allows for the first time fluxgate magnetometer measurements of ELF waves between the ion cyclotron and the lower hybrid frequencies in the equatorial dayside magnetosheath. The so-called lion roars, typically seen by the Equator-S magnetometer at the bottom of the magnetic troughs of magnetosheath mirror waves, are near-monochromatic packets of electron whistler waves lasting for a… 
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Lion roars, which are intense packets of electromagnetic waves characteristically found in the magnetosheath, have been studied. The average frequency of the emissions is 120 Hz with over 90%
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The special feature of the ringcore fluxgate magnetometer on Equator-S is the high time and field resolution. The scientific aim of the experiment is the investigation of waves in the 10–100
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