Evidence for chorus-driven electron acceleration to relativistic energies from a survey of geomagnetically disturbed periods
Meredith, N.P.; Cain, M.; Horne, R.B.; Thorne, R.M.; Summers, D.; Anderson, R.R.. 2003 Evidence for chorus-driven electron acceleration to relativistic energies from a survey of geomagnetically disturbed periods. Journal of Geophysical Research, 108 (A6), 1248. 14, pp. 10.1029/2002JA009764Full text not available from this repository. (Request a copy)
 We perform a survey of the plasma wave and particle data from the CRRES satellite during 26 geomagnetically disturbed periods to investigate the viability of a local stochastic electron acceleration mechanism to relativistic energies driven by Doppler-shifted cyclotron resonant interactions with whistler mode chorus. Relativistic electron flux enhancements associated with moderate or strong storms may be seen over the whole outer zone (3 < L < 7), typically peaking in the range 4 < L < 5, whereas those associated with weak storms and intervals of prolonged substorm activity lacking a magnetic storm signature (PSALMSS) are typically observed further out in the regions 4 < L < 7 and 4.5 < L < 7, respectively. The most significant relativistic electron flux enhancements are seen outside of the plasmapause and are associated with periods of prolonged substorm activity with AE greater than 100 nT for a total integrated time greater than 2 days or greater than 300 nT for a total integrated time greater than 0.7 days. These events are also associated with enhanced fluxes of seed electrons and enhanced lower-band chorus wave power with integrated lower-band chorus wave intensities of greater than 500 pT(2) day. No significant flux enhancements are seen unless the level of substorm activity is sufficiently high. These results are consistent with a local, stochastic, chorus-driven electron acceleration mechanism involving the energization of a seed population of electrons with energies of a few hundred keV to relativistic energies operating on a timescale of the order of days.
|Programmes:||BAS Programmes > Antarctic Science in the Global Context (2000-2005) > Magnetic Reconnection, Substorms and their Consequences|
|NORA Subject Terms:||Meteorology and Climatology
|Date made live:||11 Aug 2010 12:25|
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