Atmospheric Composition and Structure: Airglow and aurora; Magnetospheric Physics: Energetic particles: precipitating; Planetary Sciences: Solid Surface Planets: Aurorae and airglow; Space Plasma Physics: Kinetic and MHD theory; hot oxygen; escape
Abstract :
[en] The high-energy proton-hydrogen (H[SUP]+[/SUP]/H) beam associated with proton auroral precipitation transfers momentum in elastic and inelastic collisions with ambient thermal atomic oxygen in the high latitude thermosphere. This process provides a localized novel source of hot oxygen atoms in addition to exothermic photochemistry, charge exchange and momentum transfer from O[SUP]+[/SUP] ion precipitation and charge exchange with accelerated ionospheric O[SUP]+[/SUP] ions. We suggest that this source contributes to the population of the hot oxygen geocorona and to the flux of escaping oxygen atoms. For an incident proton energy flux of 1 mW m[SUP]-2[/SUP] and a mean energy E[SUB]mean[/SUB] ~ 5 keV, we calculate a density of hot oxygen atoms with energy above 1 eV of 2.0 × 10[SUP]3[/SUP] cm[SUP]-3[/SUP] and a mean kinetic energy of about 3.5 eV at 700 km. The total upward flux of hot oxygen atoms with energies higher 1 eV is estimated as 3.5 × 10[SUP]8[/SUP] cm[SUP]-2[/SUP] s[SUP]-1[/SUP].
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Shematovich, V. I.; Institute of Astronomy, Russian Academy of Sciences, Moscow, Russia) ; AB(Institute of Astronomy, Russian Academy of Sciences, Moscow, Russia) ; AC(Laboratoire de Physique Atmosphérique et Planétaire, Université de Liège, Liège, Belgium
Bisikalo, D. V.
Gérard, Jean-Claude ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Labo de physique atmosphérique et planétaire (LPAP)
Language :
English
Title :
An auroral source of hot oxygen in the geocorona
Publication date :
01 January 2005
Journal title :
Geophysical Research Letters
ISSN :
0094-8276
eISSN :
1944-8007
Publisher :
American Geophysical Union, Washington, United States - District of Columbia
Balakrishnan, N., V. Kharchenko, and A. Dalgarno (1998a), Slowing of energetic O(3P) atoms in collisions with N2, J. Geophys. Res., 103, 23,393-23,398.
Balakrishnan, N., V. Kharchenko, and A. Dalgarno (1998b), Quantum mechanical and semiclassical studies of N + N2 collisions and their application to thermalization of fast N atoms, J. Chem. Phys., 108 943-949.
Bisikalo, D. V., V. I. Shematovich, and J.-C. Gérard (1995), Kinetic model of the formation of the hot oxygen geocorona: 2. Influence of O+ ion precipitation, J. Geophys. Res., 100, 3715-3720.
Coumans, V., J.-C. Gérard, B. Hubert, S. B. Mende, and S. W. H. Cowley (2004), Morphology and seasonal variations of global auroral proton precipitation observed by IMAGE-FUV, J. Geophys. Res., 109, A12205, doi:10.1029/2003JA010348.
Gardner, L. C., and R. W. Schunk (2004), Neutral polar wind, J. Geophys. Res., 109, A05301, doi:10.1029/2003JA010291.
Gérard, J.-C., P. G. Richards, V. I. Shematovich, and D. V. Bisikalo (1995), The importance of new chemical sources for the hot oxygen geocorona, Geophys. Res. Lett., 22, 279-282.
Gérard, J.-C., B. Hubert, D. V. Bisikalo, and V. I. Shematovich (2000), A model of the Lyman-α line profile in the proton aurora, J. Geophys. Res., 105, 15,795-15,806.
Hedin, A. E. (1991), Extension of the MSIS thermosphere model into the middle and lower atmosphere, J. Geophys. Res., 96, 1159-1172.
Ishimoto, M., G. R. Romick, and C.-I. Meng (1992), Energy distribution of energetic O+ precipitation into the atmosphere, J. Geophys. Res., 97, 8619-8629.
Kharchenko, V., A. Dalgarno, B. Zygelman, and J.-H. Yee (2000), Energy transfer in collisions of oxygen atoms in the terrestrial atmosphere, J. Geophys. Res., 105, 24,899-24,906.
Richards, P. G., M. P. Hickey, and D. G. Torr (1994), New sources for the hot oxygen geocorona, Geophys. Res. Lett., 21, 657-660.
Rohrbaugh, R. P., and J. S. Nisbet (1973), Effect of energetic oxygen atoms on neutral density models, J. Geophys. Res., 78, 6768-6772.
Shematovich, V. I., D. V. Bisikalo, and J.-C. Gérard (1994), A kinetic model of the formation of the hot oxygen geocorona: 1. Quiet geomagnetic conditions, J. Geophys. Res., 99, 23,217-23,228.
Shematovich, V. I., J.-C. Gérard, D. V. Bisikalo, and B. Hubert (1999), Thermalization of O(1D) atoms in the thermosphere, J. Geophys. Res., 104, 4287-4295.
Torr, M. R., J. C. G. Walker, and D. G. Torr (1974), Escape of fast oxygen from the atmosphere during geomagnetic storms, J. Geophys. Res., 79, 5267-5271.
Wilson, G. R., T. E. Moore, and M. R. Collier (2003), Low-energy neutral atoms observed near the Earth, J. Geophys. Res., 108(A4), 1142, doi:10.1029/2002JA009643.
Yau, A., and M. André (1997), Source of ion outflow in the high latitude ionosphere, Space Sci. Rev., 80, 1-25.
Yee, J. H., J. W. Meriwether Jr., and P. B. Hays (1980), Detection of a hot corona of fast oxygen atoms during solar maxim, J. Geophys. Res., 85, 3396-3400.