Amplitude–frequency characteristics of ion–cyclotron and whistler-mode waves from Van Allen Probes data
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Using two-hour (from 2300 UT January 25, 2013 to 0100 UT January 26, 2013) measurement data from Van Allen Probes on fluxes of energetic particles, cold plasma density, and magnetic field magnitude, we have calculated the local growth rate of electromagnetic ion–cyclotron and whistler-mode waves for field-aligned propagation. The results of these calculations have been compared with wave spectra observed by the same Van Allen Probe spacecraft. The time intervals when the calculated wave increments are sufficiently large, and the frequency ranges corresponding to the enhancement peak agree with the frequency–time characteristics of observed electromagnetic waves. We have analyzed the influence of variations in the density and ionic composition of cold plasma, fluxes of energetic particles, and their pitch-angle distribution on the wave generation. The ducted propagation of waves plays an important role in their generation during the given event. The chorus VLF emissions observed in this event cannot be explained by kinetic cyclotron instability, and their generation requires much sharper changes (“steps”) for velocity distributions than those measured by energetic particle detectors on Van Allen Probes satellites.
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- Bespalov, P.A. and Trakhtengerts, V.Yu., Al’fvenovskie mazery (Alfvén Masers), Gor’kii: IPF ANSSSR, 1986.Google Scholar
- Chen, L., Bortnik, J., Li, W., Thorne, R.M., and Horne, R.B., Modeling the properties of plasmaspheric hiss: 2. Dependence on the plasma density distribution, J. Geophys. Res., 2012a, vol. 117, A05202. doi 10.1029/2011JA017202Google Scholar
- Cornilleau-Wehrlin, N., Solomon, J., Korth, A., and Kremser, G., Experimental study of the relationship between energetic electrons and elf waves observed on board GEOS-A support to quasi-linear theory, J. Geophys. Res., vol. 90, no. 5, pp. 4141–4154. doi 10.1029/JA090iA05p04141Google Scholar
- Ermakova, E.N., Yahnin, A.G., Yahnina, T.A., Demekhov, A.G., and Kotik, D.S., Sporadic geomagnetic pulsations at frequencies up to 15 Hz in the magnetic storm of November 7–14, 2004: Features of amplitude and polarization spectra and their connection with ion–cyclotron waves in the magnetosphere, Radiophys. Quantum Electron., 2015, vol. 58, no. 8, pp. 547–560.Google Scholar
- Funsten, H.O., Skoug, R.M., Guthrie, A.A., et al., Helium, oxygen, proton, and electron (HOPE) mass spectrometer for the radiation belt storm probes mission, Space Sci. Rev., 2013, vol. 179, nos. 1–4, pp. 423–484. doi 10.1007/s11214-013-9968-7Google Scholar
- Kurth, W.S., De Pascuale, S., Faden, J.B., Kletzing, C.A., Hospodarsky, G.B., Thaller, S., and Wygant, J.R., Electron densities inferred from plasma wave spectra obtained by the waves instrument on Van Allen probes, J. Geophys. Res.: Space, 2015, vol. 120, no. 2, pp. 904–914. doi 10.1002/2014JA020857CrossRefGoogle Scholar
- Titova, E.E., Kozelov, B.V., Demekhov, A.G., Manninen, J., Santolik, O., Kletzing, C.A., and Reeves, G., Identification of the source of quasiperiodic VLF emissions using ground-based and Van Allen Probes satellite observations, Geophys. Res. Lett., 2015, vol. 42, pp. 6137–6145.CrossRefGoogle Scholar