time domain structures cause electron precipitation in pulsating auroras;
chorus cannot precipitate electrons observed in pulsating auroras;
OUTER RADIATION BELT;
ELECTROSTATIC SOLITARY WAVES;
DOUBLE-LAYERS;
NUMERICAL-SIMULATION;
MAGNETIC-FIELD;
WHISTLER WAVES;
ACCELERATION;
INSTABILITIES;
GENERATION;
SATELLITE;
D O I:
10.1002/2018JA025218
中图分类号:
P1 [天文学];
学科分类号:
0704 ;
摘要:
Nishimura et al. (2010, https://doi.org/10.1126/science.1193186,2011, https://doi.org/10.1029/2011JA016876, 2013, https://doi.org/10.1029/2012JA018242), and in their comment, hereafter called N18) have suggested that chorus waves interact with equatorial electrons to produce pulsating auroras. We agree that chorus can scatter electrons >10keV, as do Time Domain Structures (TDSs). Lower-energy electrons occurring in pulsating auroras cannot be produced by chorus, but such electrons are scattered and accelerated by TDS. TDSs often occur with chorus and have power in their spectra at chorus frequencies. Thus, the absence of power at low frequencies is not evidence that TDSs are absent, as an example shows. Through examination of equatorial electric field waveforms and electron pitch angle distributions measured on the Time History of Events and Macroscale Interactions during Substorms satellites (in place of examining field and particle spectra, as done by Nishimura et al.), we show that chorus cannot produce the field-aligned electrons associated with pulsating auroras in the Nishimura et al. (2010, https://doi.org/10.1126/science.1193186)) events, but TDSs can. Equatorial field-aligned electron distributions associated with pulsating auroras and created by TDS in the absence of chorus or any other wave at the equator are also shown.
机构:
BP Exploration Ltd., Chertsey Road, Sunbury-on-Thames, Middlesex, TW16 7LN, United KingdomBullard Laboratories, Madingley Rise, Madingley Road, Cambridge, CB3 0EZ, United Kingdom
Mackay, L.M.
Jones, S.M.
论文数: 0引用数: 0
h-index: 0
机构:
School of Geography, Earth and Environmental Sciences, University of Birmingham, B15 2TT, United KingdomBullard Laboratories, Madingley Rise, Madingley Road, Cambridge, CB3 0EZ, United Kingdom