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Kitamura N, Seki K, Keika K, Nishimura Y, Hori T, Hirahara M, Lund EJ, Kistler LM, Strangeway RJ. On the relationship between energy input to the ionosphere and the ion outflow flux under different solar zenith angles. EARTH, PLANETS, AND SPACE : EPS 2021; 73:202. [PMID: 34790028 PMCID: PMC8572202 DOI: 10.1186/s40623-021-01532-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 10/17/2021] [Indexed: 06/13/2023]
Abstract
The ionosphere is one of the important sources for magnetospheric plasma, particularly for heavy ions with low charge states. We investigate the effect of solar illumination on the number flux of ion outflow using data obtained by the Fast Auroral SnapshoT (FAST) satellite at 3000-4150 km altitude from 7 January 1998 to 5 February 1999. We derive empirical formulas between energy inputs and outflowing ion number fluxes for various solar zenith angle ranges. We found that the outflowing ion number flux under sunlit conditions increases more steeply with increasing electron density in the loss cone or with increasing precipitating electron density (> 50 eV), compared to the ion flux under dark conditions. Under ionospheric dark conditions, weak electron precipitation can drive ion outflow with small averaged fluxes (~ 107 cm-2 s-1). The slopes of relations between the Poynting fluxes and outflowing ion number fluxes show no clear dependence on the solar zenith angle. Intense ion outflow events (> 108 cm-2 s-1) occur mostly under sunlit conditions (solar zenith angle < 90°). Thus, it is presumably difficult to drive intense ion outflows under dark conditions, because of a lack of the solar illumination (low ionospheric density and/or small scale height owing to low plasma temperature).
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Affiliation(s)
- Naritoshi Kitamura
- Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Kanako Seki
- Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Kunihiro Keika
- Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Yukitoshi Nishimura
- Department of Electrical and Computer Engineering and Center for Space Physics, Boston University, Boston, MA USA
| | - Tomoaki Hori
- Institute for Space-Earth Environmental Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Japan
| | - Masafumi Hirahara
- Institute for Space-Earth Environmental Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Japan
| | - Eric J. Lund
- Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, NH USA
- College Brook Scientific, Durham, NH USA
| | - Lynn M. Kistler
- Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, NH USA
- Department of Physics, University of New Hampshire, Durham, NH USA
| | - Robert J. Strangeway
- Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, CA USA
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Huang F, Chen Y, Peng HO, Zheng JG, Shi GF, Hu ZQ, Yu MY. Lower hybrid drift instability in a neutral sheet with O+ ions. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2009; 80:056401. [PMID: 20365077 DOI: 10.1103/physreve.80.056401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2009] [Revised: 09/13/2009] [Indexed: 05/29/2023]
Abstract
The electromagnetic lower-hybrid drift instability (LHDI) in the intermediate-wavelength regime k_(y)sqrt[rho_(i)rho_(e)] approximately 1 , where k_(y) and rho_(e,i) are the wave vector and the electron and ion gyroradii, respectively, in a thin plasma sheet containing electrons and H+ and O+ ions is examined using kinetic theory. It is shown that the growth rate of the LHDI first decreases and then increases with increase in the O+ content and temperature, with a minimum at a moderate level of the latter. The results can be relevant to understanding magnetic reconnection in the presence of LHDI.
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Affiliation(s)
- Feng Huang
- Department of Modern Physics, University of Science and Technology of China, 230026 Hefei, People's Republic of China
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Yao Y, Seki K, Miyoshi Y, McFadden JP, Lund EJ, Carlson CW. Effect of solar wind variation on low-energy O+populations in the magnetosphere during geomagnetic storms: FAST observations. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007ja012681] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Y. Yao
- Solar-Terrestrial Environment Laboratory; Nagoya University; Nagoya, Aichi Japan
| | - K. Seki
- Solar-Terrestrial Environment Laboratory; Nagoya University; Nagoya, Aichi Japan
| | - Y. Miyoshi
- Solar-Terrestrial Environment Laboratory; Nagoya University; Nagoya, Aichi Japan
| | - J. P. McFadden
- Space Sciences Laboratory; University of California; Berkeley California USA
| | - E. J. Lund
- Space Science Center; University of New Hampshire; Durham New Hampshire USA
| | - C. W. Carlson
- Space Sciences Laboratory; University of California; Berkeley California USA
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Ogawa Y. Simultaneous EISCAT Svalbard radar and DMSP observations of ion upflow in the dayside polar ionosphere. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2002ja009590] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Winglee RM. Global impact of ionospheric outflows on the dynamics of the magnetosphere and cross-polar cap potential. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2001ja000214] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Siscoe GL, Erickson GM, Sonnerup BUÖ, Maynard NC, Siebert KD, Weimer DR, White WW. Relation between cusp and mantle in MHD simulation. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000ja000385] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Seki K, Elphic RC, Hirahara M, Terasawa T, Mukai T. On atmospheric loss of oxygen ions from earth through magnetospheric processes. Science 2001; 291:1939-41. [PMID: 11239148 DOI: 10.1126/science.1058913] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
In Earth's environment, the observed polar outflow rate for O(+) ions, the main source of oxygen above gravitational escape energy, corresponds to the loss of approximately 18% of the present-day atmospheric oxygen over 3 billion years. However, part of this apparent loss can actually be returned to the atmosphere. Examining loss rates of four escape routes with high-altitude spacecraft observations, we show that the total oxygen loss rate inferred from current knowledge is about one order of magnitude smaller than the polar O(+) outflow rate. This disagreement suggests that there may be a substantial return flux from the magnetosphere to the low-latitude ionosphere. Then the net oxygen loss over 3 billion years drops to approximately 2% of the current atmospheric oxygen content.
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Affiliation(s)
- K Seki
- Department of Earth and Planetary Sciences, University of Tokyo, Hongo 7-3-1, Bunkyo, Tokyo 113-0033, Japan.
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Seki K, Elphic RC, Thomsen MF, Bonnell J, Lund EJ, Hirahara M, Terasawa T, Mukai T. Cold flowing O+beams in the lobe/mantle at Geotail: Does FAST observe the source? ACTA ACUST UNITED AC 2000. [DOI: 10.1029/1999ja900470] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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