Observational tests of the Ion Cyclotron Resonance Heating (ICRH)
mechanism
References
Chang et al. (1986) made a specific prediction about the relationship
between wave energy in the range of an ions local gyrofrequency and
the ion heating rate. It was possible to test this relationship
using DE/EICS data in a number of ways described in the
references below.
The figure above (from Andre et al., 1990). Shows the relationship
between:
- Electric field power spectral density in the 0-8 Hz range (top panel)
- Energetic H+ ions. (second panel) The poleward edge of the cusp is at ~01:24 and
the energy-angle dispersion of H+ energy with latitude is clearly resolved.
- Energetic O+ ions. (third panel) Transverse heating (conic formation) begins
where the wave power turns on at ~ 01:24. Peterson et al. 1989 and
Andre et al. 1990 have shown that the observed O+ energies are those
predicted by the Chang et al. relationship.
- Energetic ion pitch angle (fourth panel)
- Ambient thermal plasma (bottom panel). The disappearance of thermal
O+ occurs coincident with the onset of energetic O+. This shows that
the power level is such that the entire source O+ population is rapidly
energized.
References (In alphabetical order by first author)
-
Andre, M., G.B. Crew, W.K. Peterson, A.M. Persoon, C.J. Pollock, and M.J.
Engebretson, "Heating of ion conics in The Cusp/cleft", in Physics of Space
Plasmas (1989), SPI Conference Proceedings and Reprint Series Number 9, T.
Chang, G.B. Crew and J.R. Jasperse, eds. Scientific Publishers, Cambridge MA,
P. 203, 1990a.
-
Andre, M., G.B. Crew, W.K. Peterson, A.M. Persoon, C.J. Pollock, and M.S.
Engebretson, Heating by Broadband Low-Frequency, Waves in the Cusp/cleft, J.
Geophys. Res., 95, 20809, 1990.
-
Ball, L., and M. Andre, Heating of 0+ ions in the cusp/cleft: Double-cyclotron
absorption versus cyclotron resonance, J. Geophys. Res., 96, 1429, 1991.
-
Chang, T., C. B. Crew, N. Herskowitz, J. R. Jasperse, J. M. Retterer, and J.
D. Winningham, Transverse acceleration of oxygen ions by electromagnetic ion
cyclotron resonance with broad band left-hand polarized waves, Geophys. Res.
Lett., 13, 636, 1986.
-
Crew, G. B., T. Chang, J. M. Retterer, W. K. Peterson, D. A. Gurnett, and R.
L. Hutt, Ion cyclotron resonance heated conics: Theory and observations, J.
Geophys. Res. 95, 3959, 1990.
-
Peterson, W. K., M. Andre, G. B. Crew, A. M. Persoon, M. J. Engebretson, C. J.
Pollock, and M. Temerin, Heating of thermal ions near the equatorward boundary
of the mid-altitude polar cleft, in Electrodynamic Coupling in the Polar
Clefts and Caps, P. E. Sandholt and A. Egeland Editors Kluwer Academic
Publishers, p. 103, 1989.
Last updated October, 1995 by W.K. Peterson