Magnetospheric Physics: Auroral phenomena (2407); Magnetospheric Physics: Storms and substorms; Magnetospheric Physics: Energetic particles; precipitating; Magnetospheric Physics: Current systems (2409)
Abstract :
[en] Images from the IMAGE Wide-band Imaging Camera (WIC) and Spectrographic Imager (SI) channels SI-12 and SI-13 were compared to in situ data taken by FAST during several substorms. FAST spacecraft observations have shown that the high latitude auroral ionosphere has several distinct regions. Intense auroras are seen in regions of upward directed quasi static electric fields and of Alfven wave accelerated superthermal electrons. In two of the cases presented, the satellite passed through an active poleward propagating substorm surge on its duskward flank. Both show that the superthermal wave accelerated component to be on the polar cap boundary of the surge, and that it could be distinguished from quasi static field ``inverted V'' precipitation which occurred at the more equatorward parts of the auroral oval. In one of these cases, the surge was accompanied by intense ion outflow. Three cases showed the FAST satellite passing through the substorm aurora at midnight or the dawn side outside of the surge and the wave accelerated electrons were less clearly separated from the inverted V type precipitation. The wave accelerated electrons were seen to be part of very short-lived transient events, i.e., bursts. The region of auroral forms, associated with Alfven waves exhibit relatively soft auroral precipitation with very intense electron fluxes. By comparing the intensity of the WIC and SI-13 channels of IMAGE FUV, it is possible sometimes to distinguish optically between the two types of regions. Global imaging of the two regions would allow the separation of quasi-static plasma convection regions containing inverted V-s from regions of Alfven wave driven electrons signifying substorm related magnetic field dynamics.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Mende, S. B.
Carlson, C. W.
Frey, H. U.
Immel, T. J.
Gérard, Jean-Claude ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Labo de physique atmosphérique et planétaire (LPAP)
Language :
English
Title :
IMAGE FUV and in situ FAST particle observations of substorm aurorae
Publication date :
01 March 2003
Journal title :
Journal of Geophysical Research. Space Physics
ISSN :
2169-9380
eISSN :
2169-9402
Publisher :
American Geophysical Union (AGU), Washington, United States - District of Columbia
Boehm, M. H., J. Clemmons, J.-E. Wahlund, A. Eriksson, L. Eliasson, L. Blomberg, P. Kintner, and H. Hofner, Observations of an upward-directed electron beam with the perpendicular temperature of the cold ionosphere, Geophys. Res. Lett., 22, 2103, 1995.
Burch, J. L., Diagnosis of auroral acceleration mechanisms by particle measurements in Auroral Physics, edited by C.-I. Meng, M. J. Rycroft, L. A. Frank, Cambridge Univ. Press, New York, 1991.
Carlson, C. W., et al., FAST observations in the downward auroral current region: energetic upgoing electron beams, parallel potential drops, and ion heating, Geophys. Res. Lett., 25, 2017, 1998.
Chaston, C. C. C. W. Carlson, R. E. Ergun, and J. P. McFadden, Alfven waves, density cavities and electron acceleration observed from the FAST spacecraft, Phys. Scripta, T84, 64-68, 2000.
Chaston, C. C, W. J. Peria, C. W. Carlson, R. E. Ergun, and. J. P. McFadden, FAST observations of Inertial Alfven waves and electron acceleration in the dayside aurora, Phys. Chem. Earth, 26, 201, 2001a.
Chaston, C. C, J. W. Bonnell, L. M. Peticolas, C. W. Carlson, J. P. McFadden, and R. E. Ergun, Driven Alfven waves and electron acceleration: A FAST case study, Geophys. Res. Lett., 29(11), 1535, doi:10.1029/ 2001GL013842, 2002.
Elphinstone, R. D., et al., The double oval UV auroral distribution, I, Implications for the mapping of auroral arcs, J. Geophys. Res., 100, 12,075, 1995a.
Elphinstone, R. D., et al., The double oval UV auroral distribution, 2, The most poleward arc system and the dynamics of the magnetotail, J. Geophys. Res., 100, 12,093, 1995b.
Ergun, R. E., et al., FAST satellite observations of electric field structures in the auroral zone, Geophys. Res. Lett., 25, 20,025, 1998.
Evans, D. S., Precipitating electron fluxes formed by a magnetic field aligned potential difference, J. Geophys. Res., 79, 2853, 1974.
Frank, L. A., and K. L. Ackcrson, Observations of charged particle precipitation into the auroral zone, J. Geophys. Res., 76, 3612, 1971.
Frey, H. U., S. B. Mende, H. B. Vo, M. Brittnacher, and G. K. Parks, Conjugate observation of optical aurora with Polar satellite and ground-based cameras, Adv. Space Res., 23, 1647, 1999.
Frey, H. U., S. B. Mende, C. W. Carlson, J. C. Gérard, B. Hubert, J. Spann, R. Gladstone, and T. J. Immel, The electron and proton aurora as seen by IMAGE-FUVand FAST, Geophys. Res. Lett., 28, 1135, 2001.
Gary, J. B., L. J. Zanetti, B. J. Anderson, T. A. Potemra, J. H. Clemmons, J. D. Winningham, and J. R. Sharber, Identification of auroral oval boundaries from in situ magnetic field measurements, J. Geophys. Res., 103, 4187, 1998.
Gérard, J. C, B. Hubert, D. V. Bisikalo, V. I. Shematovich, H. U. Frey, S. B-Mende, and G. R. Gladston, Observation of the FUV proton aurora from the IMAGE satellite, J. Geophys. Res., 106, 28,939, 2001.
Hubert, B., J.-C. Gérard, D. S. Evans, M. Meurant, S. B. Mende, H. U. Frey, and T. J. Immel, Total electron and proton energy input during auroral substorms: Remote sensing with IMAGE-FUV, J. Geophys. Res., 107(A8), 10.1029/2001JA009229, 2002.
Johnstone, A. D., and J. D. Winningham, Satellite observations of su-prathermal electron bursts, J. Geophys. Res., 87, 2321, 1982.
Keiling, A., J. R. Wygant, C. Cattell, M. Temerin, F. S. Mozer, C. A. Kletzing, J. Scudder, C. T. Russell, W. Lotko, and A. V. Streltsov, Large Alfven wave power in the plasma sheet boundary layer during the expansion phase of substorms, Geophys. Res. Lett., 27, 3169, 2000.
Knudsen, D. J., J. H. Clemmons, and J.-E. Wahlund, Correlation between core ion energization, suprathermal electron bursts, and broadband ELF plasma waves, J. Geophys. Res., 103, 4171, 1998.
Lopez, R. E., H. E. Spence, and C.-I. Meng, DMSP F7 observations of a substorm field-aligned current, J. Geophys. Res., 96, 19,409, 1991.
McFadden, J. P., C. W. Carlson, and R. E. Ergun, Microstructure of the auroral acceleration region as observed by FAST, J. Geophys. Res., 104, 14,453, 1999.
Mende, S. B., et al., Far ultraviolet imaging from the IMAGE spacecraft, 1, System design, Space Sci. Rev., 91, 243, 2000.
Mende, S. B., H. U. Frey, M. Lampton, J.-C. Gérards, B. Hubert, S. A. Fuselier, J. Spann, R. Gladstone, and J. L. Burch, Global observations of proton and electron auroras in a substorm, Geophys. Res. Lett., 28, 1139, 2001.
Newell, P. T., Reconsidering the inverted-V particle signature: Relative frequency of large-scale electron acceleration events, J. Geophys. Res., 105, 15,779, 2000.
Stasiewicz, K., G. Gustafsson, G. Marklund, P.-A. Lindqvist, J. Clemmons, and L. Zanetti, Cavity resonators and Alfven resonance cones observed on Freja, J. Geophys. Res., 102, 2565, 1997.
Stasiewicz, K., G. Holmgren, and L. Zanetti, Density depletions and current singularities observed by Freja, J. Geophys. Res., 103, 4251, 1998.
Stasiewicz, K., et al., Small scale alfvenic structure in the aurora, Space Sci. Rev., 92, 423-533, 2000.
Temerin, M., C. Carlson, and J. McFadden, Auroral particle acceleration, in Proceedings of the International Conference on Substorms-2, edited by J. R. Kan, J. D. Craven, and S.-I. Akasofu, p. 375, Univ. of Alaska, Fairbanks, 1994.
Tung, Y.-K., C. W. Carlson, J. P. McFadden, D. M. Klumpar, G. K. Parks, W. J. Peria, and K. Liou, Auroral polar cap boundary ion conic outflow observed on FAST, J. Geophys. Res., 106, 3603, 2001.
Wahlund, J.-E., et al., Broadband ELF plasma emission during auroral energization, 1, Slow ion acoustic waves, J. Geophys. Res., 103,4343,1998.
Wygant, J. R., et al., Polar spacecraft based comparisons of intense electric fields and Poynting flux near and within the plasma sheet-tail lobe boundary to UVI images: An energy source for the aurora, J. Geophys. Res., 105, 18,675, 2000.
