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Modeling Earth's Radiation Belt Electron Dynamics

Earth's radiation belt electrons are also known as "killer" electrons, since they can potentially damage critical electronics or cause anomalies of satellites. Using multi-satellite observations (e.g., Van Allen Probes, THEMIS, etc.) and simulation, we are studying the physical processes responsible for Earth's radiation belt electron acceleration, loss, and transport.

Van Allen Probes mission [Credit: NASA]

Schematic illustration of local electron acceleration by chorus and radial diffusion

[Thorne et al., Nature, 2013]

Selected Publications on This Topic

  • Li, W., Y. Y. Shprits, and R. M. Thorne (2007), Dynamic evolution of energetic outer zone electrons due to wave-particle interactions during storms, J. Geophys. Res., 112, A10220, doi:10.1029/2007JA012368.

  • Li, W., et al. (2014), Radiation belt electron acceleration by chorus waves during the 17 March 2013 storm, J. Geophys. Res. Space Physics, 119, 4681–4693, doi:10.1002/2014JA019945.

  • Li, W., et al. (2016), Radiation belt electron acceleration during the 17 March 2015 geomagnetic storm: Observations and simulations, J. Geophys. Res. Space Physics, 121,5520–5536, doi:10.1002/2016JA022400.

  • Thorne, R. M., W. Li, B. Ni, Q. Ma, J. Bortnik, L. Chen, D. N. Baker, H. E. Spence, G. D. Reeves, M. G. Henderson, C. A. Kletzing, W. S. Kurth, G. B. Hospodarsky, J. B. Blake, J. F. Fennell, S. G. Claudepierre, and S. G. Kanekal (2013), Rapid local acceleration of relativistic radiation belt electrons by magnetospheric chorus, Nature, 504, 411-414, doi:10.1038/nature12889.

  • Thorne, R. M., W. Li, B. Ni, Q. Ma, J. Bortnik, D. N. Baker, H. E. Spence, G. D. Reeves, M. G. Henderson, C. A. Kletzing, W. S. Kurth, G. B. Hospodarsky, D. Turner, and V. Angelopoulos (2013), Evolution and slow decay of an unusual narrow ring of relativistic electrons near L ~ 3.2 following the September 2012 magnetic storm, Geophys. Res. Lett., 40, 3507–3511, doi:10.1002/grl.50627.

  • Ma, Q., W. Li, R. M. Thorne, B. Ni, C. A. Kletzing, W. S. Kurth, G. B. Hospodarsky, G. D. Reeves, M. G. Henderson, H. E. Spence, D. N. Baker, J. B. Blake, J. F. Fennell, S. G. Claudepierre, and V. Angelopoulos (2015), Modeling inward diffusion and slow decay of energetic electrons in the Earth’s outer radiation belt, Geophys. Res. Lett., 42, 987-995, doi: 10.1002/2014GL062977.

  • Ma, Q., W. Li, R. M. Thorne, J. Bortnik, C. A. Kletzing, W. S. Kurth, and G. B. Hospodarsky (2016), Electron scattering by magnetosonic waves in the inner magnetosphere, J. Geophys. Res. Space Physics, 121, 274-285, doi:10.1002/2015JA021992.

  • Ma, Q., W. Li, R. M. Thorne, Y. Nishimura, X.-J. Zhang, G. D. Reeves, C. A. Kletzing, W. S. Kurth, G. B. Hospodarsky, M. G. Henderson, et al. (2016), Simulation of energy-dependent electron diffusion processes in the Earth's outer radiation belt, J. Geophys. Res. Space Physics, 121, 4217–4231, doi:10.1002/2016JA022507.

  • Zhang, X.-J., W. Li, R. M. Thorne, V. Angelopoulos, Q. Ma, J. Li, J. Bortnik, L. Chen, D. N. Baker, G. D. Reeves, H. E. Spence, C. A. Kletzing, W. S. Kurth, G. B. Hospodarsky, J. B. Blake, and J. F. Fennell (2016), Physical mechanism causing rapid changes in ultrarelativistic electron pitch angle distributions right after a shock arrival: Evaluation of an electron dropout event, J. Geophys. Res. Space Physics,121, doi:10.1002/2016JA022517.

  • Li, J., J. Bortnik, R. M. Thorne, W. Li, Q. Ma, D. N. Baker, G. D. Reeves, J. F. Fennell, H. E. Spence, C. A. Kletzing, W. S. Kurth, G. B. Hospodarsky, V. Angelopoulos, and J. B. Blake (2016), Ultrarelativistic electron butterfly distributions created by parallel acceleration due to magnetosonic waves, J. Geophys. Res. Space Physics, 121, 3212–3222, doi:10.1002/2016JA022370.

  • Zhang, X.-J., W. Li, R. M. Thorne, V. Angelopoulos, Q. Ma*, J. Li, J. Bortnik, L. Chen, D. N. Baker, G. D. Reeves, H. E. Spence, C. A. Kletzing, W. S. Kurth, G. B. Hospodarsky, J. B. Blake, and J. F. Fennell (2016), Physical mechanism causing rapid changes in ultrarelativistic electron pitch angle distributions right after a shock arrival: Evaluation of an electron dropout event, J. Geophys. Res. Space Physics, 121, 8300–8316, doi:10.1002/2016JA022517.

  • Ma, Q.*, W. Li, R. M. Thorne, J. Bortnik, G. D. Reeves, C. A. Kletzing, W. S. Kurth, G. B. Hospodarsky, H. E. Spence, D. N. Baker, J. B. Blake, J. F. Fennell, S. G. Claudepierre, and V. Angelopoulos (2016), Characteristic energy range of electron scattering due to plasmaspheric hiss, J. Geophys. Res. Space Physics, 121, 11,737–11,749, doi:10.1002/2016JA023311.

  • Mourenas, D., Q. Ma*, A. V. Artemyev, and W. Li (2017), Scaling laws for the inner structure of the radiation belts, Geophys. Res. Lett., 44, 3009–3018, doi:10.1002/2017GL072987.

  • Wang, C., Ma, Q.*, Tao, X., Zhang, Y., Teng, S., Albert, J. M., Chan, A. A., Li, W., Ni, B., Lu, Q. and Wang, S. (2017), Modeling radiation belt dynamics using a 3D layer method code. J. Geophys. Res. Space Physics, 122, 8642–8658, doi:10.1002/2017JA024143.

  • Ma, Q.*, Li, W., Thorne, R. M., Bortnik, J., Reeves, G. D., Spence, H. E., … Baker, D. N. (2017). Diffusive transport of several hundred keV electrons in the Earth's slot region. Journal of Geophysical Research: Space Physics, 122, 10,235–10,246. https://doi.org/10.1002/2017JA024452.

  • Kang, S.‐B., Fok, M.‐C., Komar, C., Glocer, A., Li, W., & Buzulukova, N. (2018). An energetic electron flux dropout due to magnetopause shadowing on 1 June 2013. Journal of Geophysical Research: Space Physics, 123, 1178–1190. https://doi.org/10.1002/2017JA024879.

  • Ma, Q.*, Li, W., Bortnik, J., Thorne, R. M., Chu, X., Ozeke, L. G., et al. (2018). Quantitative evaluation of radial diffusion and local acceleration processes during GEM challenge events. Journal of Geophysical Research: Space Physics, 123, 1938–1952. https://doi.org/10.1002/2017JA025114.

  • Horne, R. B., M. W. Phillips, S. A. Glauert, N.P. Meredith, A. Hands, K. Ryden, and W. Li. (2018), Realistic worst case for a severe space weather event driven by a fast solar wind stream, Space Weather, 16, 1202–1215. https://doi.org/10.1029/2018SW001948

  • Bortnik, J., X. Chu, Q. Ma*, W. Li, X. Zhang, R. M. Thorne et al. (2018), Artificial neural networks for determining magnetospheric conditions, Machine Learning Techniques for Space Weather, pages 279–300, https://doi.org/10.1016/B978-0-12-811788-0.00011-1.

  • Tu, W., Li, W., Albert, J. M., & Morley, S. K. (2019). Quantitative assessment of radiation belt modeling. Journal of Geophysical Research: Space Physics, 124, 898– 904. https://doi.org/10.1029/2018JA026414

  • Hua, M., Ni, B., Li, W., Gu, X., Fu, S., Shi, R.*, et al. (2019). Evolution of radiation belt electron pitch angle distribution due to combined scattering by plasmaspheric hiss and magnetosonic waves. Geophysical Research Letters, 46, 3033–3042. https://doi.org/10.1029/2018GL081828

  • Katsavrias, C., Daglis, I. A., and W. Li (2019), On the statistics of acceleration and loss of relativistic electrons in the outer radiation belt: a superposed epoch analysis, J. Geophys. Res. Space Physics, 124, 2755–2768 https://doi.org/10.1029/2019JA026569

  • Katsavrias, C., Sandberg, I., Li, W., Podladchikova, O., Daglis, I. A., Papadimitriou, C., et al. (2019). Highly relativistic electron flux enhancement during the weak geomagnetic storm of April–May 2017. Journal of Geophysical Research: Space Physics, 124, 4402– 4413. https://doi.org/10.1029/2019JA026743

  • Hua, M., Li, W., Ma, Q.*, Ni, B., Nishimura, Y., Shen, X.‐C.*, & Li, H.* (2019). Modeling the electron flux enhancement and butterfly pitch angle distributions on L shells < 2.5. Geophysical Research Letters, 46, 10967– 10976. https://doi.org/10.1029/2019GL084822

  • Li, W., & Hudson, M. K. (2019). Earth's Van Allen Radiation Belts: From Discovery to the Van Allen Probes Era. Journal of Geophysical Research: Space Physics, 124, 8319–8351. https://doi.org/10.1029/2018JA025940

  • Gan, L., Li, W., Ma, Q.*, Albert, J. M., Artemyev, A. V., & Bortnik, J. (2020). Nonlinear Interactions Between Radiation Belt Electrons and Chorus Waves: Dependence on Wave Amplitude Modulation. Geophysical Research Letters, 47, e2019GL085987. https://doi.org/10.1029/2019GL085987

  • Martinez‐Calderon, C., Bortnik, J., Li, W., Spence, H., Claudepierre, S. G., Douma, E., & Rodger, C. J. (2020). Comparison of long term lightning activity and inner radiation belt electron flux perturbations. Journal of Geophysical Research: Space Physics, 125, e2019JA027763. https://doi.org/10.1029/2019JA027763

  • Li, W., Ma, Q.*, Bortnik, J. and Thorne, R. M. (2020). Recent Advances in Understanding Radiation Belt Electron Dynamics Due to Wave–Particle Interactions. In Dayside Magnetosphere Interactions (eds Q. Zong, P. Escoubet, D. Sibeck, G. Le and H. Zhang). doi:10.1002/9781119509592.ch12

  • Gan, L., Li, W., Ma, Q., Artemyev, A. V., & Albert, J. M. (2020). Unraveling the formation mechanism for the bursts of electron butterfly distributions: Test particle and quasilinear simulations. Geophysical Research Letters, 47, e2020GL090749. https://doi.org/10.1029/2020GL090749.

  • Hua, M., Li, W., Ni, B. et al. (2020). Very-Low-Frequency transmitters bifurcate energetic electron belt in near-earth space. Nature Communication, 11, 4847 (2020). https://doi.org/10.1038/s41467-020-18545-y.

  • Hua, M.*, Ni, B., Li, W., Ma, Q., Gu, X., Fu, S., et al. (2020). Statistical Distribution of Bifurcation of Earth's Inner Energetic Electron Belt at tens of keV. Geophysical Research Letters, 47, e2020GL091242. https://doi.org/10.1029/2020GL091242.

  • Teng, S., Liu, N., Ma, Q., Tao, X., & Li, W. (2021). Direct Observational Evidence of the Simultaneous Excitation of Electromagnetic Ion Cyclotron Waves and Magnetosonic Waves by an Anisotropic Proton Ring Distribution. Geophysical Research Letters, 48, e2020GL091850. https://doi.org/10.1029/2020GL091850.

  • Li, H.*, Li, W., Ma, Q.*, Nishimura, Y., Yuan, Z., Boyd, A. J., Shen, X.*, Tang, R., and Deng, X. (2021). Attenuation of plasmaspheric hiss associated with the enhanced magnetospheric electric field. Ann. Geophys., 39, 461–470, https://doi.org/10.5194/angeo-39-461-2021.

  • Artemyev. A., A. I. Neishtadt, J. M. Albert, L. Gan, W. Li, and Q. Ma (2021). Theoretical model of the nonlinear resonant interaction of whistler-mode waves and field-aligned electrons. Physics of Plasmas, 28, 052902, https://doi.org/10.1063/5.0046635.

  • Ma, Q.*, Li, W., Zhang, X.-J., Bortnik, J., Shen, X.-C.*, Connor, H. K., et al. (2021).  Global Survey of Electron Precipitation due to Hiss Waves in the Earth's Plasmasphere and Plumes. Journal of Geophysical Research: Space Physics, 126, e2021JA029644. https://doi.org/10.1029/2021JA029644.

  • Albert, J. M., Artemyev, A. V., Li, W., Gan, L., & Ma, Q.* (2021).  Models of resonant wave-particle interactions. Journal of Geophysical Research: Space Physics, 126, e2021JA029216. https://doi.org/10.1029/2021JA029216.

  • Gan, L., Li, W., Ma, Q., Artemyev, A. V., & Albert, J. M. (2022).  Dependence of nonlinear effects on whistler-mode wave bandwidth and amplitude: A perspective from diffusion coefficients. Journal of Geophysical Research: Space Physics, 127, e2021JA030063. https://doi.org/10.1029/2021JA030063.

  • Albert, J. M., Artemyev, A., Li, W., Gan, L. and Ma, Q. (2022), Equations of Motion Near Cyclotron Resonance. Front. Astron. Space Sci.9:910224. doi: 10.3389/fspas.2022.910224.

  • Ma, Q., Gu, W., Claudepierre, S. G., Li, W., Bortnik, J., Hua, M., & Shen, X.-C. (2022).  Electron scattering by very-low-frequency and low-frequency waves from ground transmitters in the Earth's inner radiation belt and slot region. Journal of Geophysical Research: Space Physics, 127, e2022JA030349. https://doi.org/10.1029/2022JA030349.

  • Nasi, A, Katsavrias, C, Daglis, IA, Sandberg, I, Aminalragia-Giamini, S, Li, W, Miyoshi, Y, Evans, H, Mitani, T, Matsuoka, A, Shinohara, I, Takashima, T, Hori, T and Balasis, G (2022). An event of extreme relativistic and ultra-relativistic electron enhancements following the arrival of consecutive corotating interaction regions: Coordinated observations by Van Allen Probes, Arase, THEMIS and Galileo satellites. Front. Astron. Space Sci. 9:949788. doi: 10.3389/fspas.2022.949788.

  • Albert, J. M., Artemyev, A., Li, W., Gan, L. and Ma, Q. (2022). Analytical results for phase bunching in the pendulum model of wave-particle interactions. Front. Astron. Space Sci. 9:971358. doi: 10.3389/fspas.2022.971358.

  • Huang, S., Li, W., Shen, X.-C., Ma, Q., Chu, X., Ma, D., et al. (2022).  Application of recurrent neural network to modeling Earth's global electron density. Journal of Geophysical Research: Space Physics, 127, e2022JA030695. https://doi.org/10.1029/2022JA030695.

  • Lyu, X., Ma, Q., Tu, W., Li, W., & Capannolo, L. (2022).  Modeling the simultaneous dropout of energetic electrons and protons by EMIC wave scattering. Geophysical Research Letters, 49, e2022GL101041. https://doi.org/10.1029/2022GL101041.

  • Peng, Y., Ma, Q., Li, W., Gan, L., & Shen, X.-C. (2022). Multi-event analysis of the correlation between chorus waves and electron butterfly distribution using Van Allen Probes observation. Journal of Geophysical Research: Space Physics, 127, e2022JA030806. https://doi.org/10.1029/2022JA030806

  • Hanzelka M.*, Li, W. and Ma, Q. (2023) Parametric analysis of pitch angle scattering and losses of relativistic electrons by oblique EMIC waves. Front. Astron. Space Sci. 10:1163515. doi: 10.3389/fspas.2023.1163515

  • Huang, S., Li, W., Ma, Q., Shen, X.-C., Capannolo, L., Hanzelka, M., Chu, X., Ma, D., Bortnik, J. and Wing, S. (2023), Deep learning model of hiss waves in the plasmasphere and plumes and their effects on radiation belt electrons. Front. Astron. Space Sci. 10:1231578. doi: 10.3389/fspas.2023.1231578.

  • Hanzelka, M.*, Li, W., Ma, Q., Qin, M., Shen, X.-C., Capannolo, L. and Gan, L.* (2023). Full-wave modeling of EMIC wave packets: ducted propagation and reflected waves. Front. Astron. Space Sci. 10:1251563. doi: 10.3389/fspas.2023.1251563.

  • Hanzelka, M.*, Li, W., Qin, M., Capannolo, L., Shen, X., Ma, Q., et al. (2024). Sub-MeV electron precipitation driven by EMIC waves through nonlinear fractional resonances. Geophysical Research Letters, 51, e2023GL107355. https://doi.org/10.1029/2023GL107355

  • Michael, A. T., Sorathia, K. A., Ukhorskiy, A. Y., Albert, J., Shen, X., Li, W., & Merkin, V. G. (2024). Cross-scale modeling of storm-time radiation belt variability. Journal of Geophysical Research: Space Physics, 129, e2023JA032175. https://doi.org/10.1029/2023JA032175

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