Journal of Astronomy and Space Sciences

The Korean Space Science Society (한국우주과학회)
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A Substorm Injection Event and the Radiation Belt Structure Observed by Space Radiation Detectors onboard Next Generation Small Satellite-1 (NEXTSat-1)

  • Yoo, Ji-Hyeon (Department of Astronomy and Space Science, Chungbuk National University) ;
  • Lee, Dae-Young (Department of Astronomy and Space Science, Chungbuk National University) ;
  • Kim, Eojin (Satellite Technology Research Center, Korea Advanced Institute of Science and Technology) ;
  • Seo, Hoonkyu (Satellite Technology Research Center, Korea Advanced Institute of Science and Technology) ;
  • Ryu, Kwangsun (Satellite Technology Research Center, Korea Advanced Institute of Science and Technology) ;
  • Kim, Kyung-Chan (Department of Astronomy and Space Science, Chungbuk National University) ;
  • Min, Kyoungwook (Department of Physics, Korea Advanced Institute of Science and Technology) ;
  • Sohn, Jongdae (Korea Astronomy and Space Science Institute) ;
  • Lee, Junchan (Satellite Technology Research Center, Korea Advanced Institute of Science and Technology) ;
  • Seon, Jongho (School of Space Research, Kyung Hee University) ;
  • Kang, Kyung-In (Satellite Technology Research Center, Korea Advanced Institute of Science and Technology) ;
  • Lee, Seunguk (Department of Astronomy and Space Science, Chungbuk National University) ;
  • Park, Jaeheung (Korea Astronomy and Space Science Institute) ;
  • Shin, Goo-Hwan (Satellite Technology Research Center, Korea Advanced Institute of Science and Technology) ;
  • Park, SungOg (Satellite Technology Research Center, Korea Advanced Institute of Science and Technology)
  • Received : 2021.02.02
  • Accepted : 2021.02.24
  • Published : 2021.03.15
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Abstract

In this paper, we present observations of the Space Radiation Detectors (SRDs) onboard the Next Generation Small Satellite-1 (NEXTSat-1) satellite. The SRDs, which are a part of the Instruments for the study of Stable/Storm-time Space (ISSS), consist of the Medium-Energy Particle Detector (MEPD) and the High-Energy Particle Detector (HEPD). The MEPD can detect electrons, ions, and neutrals with energies ranging from 20 to 400 keV, and the HEPD can detect electrons over an energy range from 0.35 to 2 MeV. In this paper, we report an event where particle flux enhancements due to substorm injections are clearly identified in the MEPD A observations at energies of tens of keV. Additionally, we report a specific example observation of the electron distributions over a wide energy range in which we identify electron spatial distributions with energies of tens to hundreds of keV from the MEPD and with energy ranging up to a few MeV from the HEPD in the slot region and outer radiation belts. In addition, for an ~1.5-year period, we confirm that the HEPD successfully observed the well-known outer radiation belt electron flux distributions and their variations in time and L shell in a way consistent with the geomagnetic disturbance levels. Last, we find that the inner edge of the outer radiation belt is mostly coincident with the plasmapause locations in L, somewhat more consistent at subrelativistic energies than at relativistic energies. Based on these example events, we conclude that the SRD observations are of reliable quality, so they are useful for understanding the dynamics of the inner magnetosphere, including substorms and radiation belt variations.

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References

  1. Cho J, Lee DY, Kim JH, Shin DK, Kim KC, et al., New model fit functions of the plasmapause location determined using THEMIS observations during the ascending phase of solar cycle 24, J. Geophys. Res. Space Phys. 120, 2877-2889 (2015). http://doi.org/10.1002/2015JA021030
  2. Choi CR, Sohn J, Lee JC, Seo YM, Kang SB, et al., Scientific missions and technologies of the ISSS on board the NEXTSat-1, J. Astron. Space Sci. 31, 73-81 (2014). http://doi.org/10.5140/JASS.2014.31.1.73
  3. Jaynes AN, Baker DN, Singer HJ, Rodriguez JV, Loto'aniu TM, et al., Source and seed populations for relativistic electrons: their roles in radiation belt changes, J. Geophys. Res. Space Phys. 120, 7240-7254 (2015). https://doi.org/10.1002/2015JA021234
  4. Kim E, Yoo JH, Kim HE, Seo H, Ryu K, et al., Initial operation and preliminary results of the instrument for the study of stable/storm-time space (ISSS) on board the next generation small satellite-1 (NEXTSat-1), J. Astron. Space Sci. 37, 209-218 (2020). https://doi.org/10.5140/JASS.2020.37.3.209
  5. Kim KC, Shprits Y, Wang D, Quantifying the effect of plasmaspheric hiss on the electron loss from the slot region, J. Geophys. Res. Space Phys. 125 (2020). http://doi.org/10.1029/2019JA027555
  6. Kress BT, Rodriguez JV, Onsager TG, The GOES-R space environment in situ suite (SEISS): measurement of energetic particles in geospace, in The GOES-R Series: a new generation of geostationary environmental satellites, eds. Goodman S, Schmit TJ, Daniels JM, Redmond RJ (Elsevier, Amsterdam, 2020), 243-250.
  7. Lee DY, Recent progress in the theoretical understanding of relativistic electron scattering and precipitation by electromagnetic ion cyclotron waves in the Earth's inner magnetosphere, J. Astron. Space Sci. 36, 45-60 (2019). https://doi.org/10.5140/JASS.2019.36.2.45
  8. Lee DY, Shin DK, Kim JH, Cho JH, Kim KC, et al., Long-term loss and re-formation of the outer radiation belt, J. Geophys. Res. Space Phys. 118, 3297-3313 (2013). http://doi.org/10.1002/jgra.50357
  9. Lee J, Min K, Ryu K, Kang KI, Shin GH, et al., Space plasma detectors on NEXTSat-1 for ionospheric measurements, J. Korean Phys. Sci. 72, 1393-1401 (2018). https://doi.org/10.3938/jkps.72.1393
  10. Li X, Baker DN, O'Brien TP, Xie L, Zong QG, Correlation between the inner edge of outer radiation belt electrons and the innermost plasmapause location, Geophys. Res. Lett. 33, L14107 (2006). http://doi.org/10.1029/2006GL026294
  11. Loto'aniu PTM, Califf S, Redmon RJ, Singer HJ, Magnetic field observations from the GOES-R series, in The GOES-R Series: a new generation of geostationary environmental satellites, eds. Goodman S, Schmit TJ, Daniels JM, Redmond RJ (Elsevier, Amsterdam, 2020), 251-259.
  12. Reeves GD, Friedel RHW, Larsen BA, Skoug RM, Funsten HO, et al., Energy-dependent dynamics of keV to MeV electrons in the inner zone, outer zone, and slot regions, J. Geophys. Res. Space Phys. 121, 397- 412 (2016). http://doi.org/10.1002/2015JA021569
  13. Shin GH, Chae JS, Lee SH, Min KW, Sohn JD, et al., Operational concept of the NEXTSat-1 for science mission and space core technology verification, J. Astron. Space Sci. 31, 67-72 (2014). https://doi.org/10.5140/JASS.2014.31.1.67
  14. Shprits YY, Drozdov AY, Spasojevic M, Kellerman AC, Usanova ME, et al., Wave-induced loss of ultra-relativistic electrons in the Van Allen radiation belts, Nat. Commun. 7, 12883 (2016). https://doi.org/10.1038/ncomms12883
  15. Sohn J, Lee J, Min K, Lee J, Lee S, et al., HEPD on NEXTSat-1: a high energy particle detector for measurements of precipitating radiation belt electrons, J. Korean Phys. Soc. 72, 1086-1093 (2018). https://doi.org/10.3938/jkps.72.1086
  16. Summers D, Thorne RM, Relativistic electron pitch-angle scattering by electromagnetic ion cyclotron waves during geomagnetic storms, J. Geophys. Res. 108, 1143 (2003). http://doi.org/10.1029/2002JA009489