Scattering rates of inner belt protons by EMIC waves: A comparison between test particle and diffusion simulations

Authors

  • M. de Soria-Santacruz,

    1. Department of Aeronautics and Astronautics, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
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  • K. G. Orlova,

    1. Department of Earth and Space Sciences, UCLA, Los Angeles, California, USA
    2. Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, Moscow, Russia
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  • M. Martinez-Sanchez,

    1. Department of Aeronautics and Astronautics, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
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  • Y. Y. Shprits

    1. Department of Earth and Space Sciences, UCLA, Los Angeles, California, USA
    2. Skolkovo Institute of Science and Technology, Moscow, Russia
    3. Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
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Corresponding author: M. de Soria-Santacruz, Department of Aeronautics and Astronautics, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Room 37-375, Cambridge, MA 02139, USA. (mdesoria@mit.edu)

Abstract

[1] Inner belt energetic protons are a hindrance to development of space technologies. The emission of electromagnetic ion cyclotron (EMIC) waves from spaceborne transmitters has been proposed as a way to solve this problem. The interaction between particles and narrowband emissions has been typically studied using nonlinear test particle simulations. We show that this formulation results in a random walk of the inner belt protons in velocity space. In this paper we compute bounce-averaged pitch angle diffusion rates from test particle simulations and compare them to those of quasi-linear theory for quasi-monochromatic EMIC waves interacting with inner belt protons. We find that the quasi-linear solution is not sensitive to the frequency bandwidth for narrow distributions. Bounce-averaged diffusion coefficients from both approaches are in good agreement for all energies and pitch angles. The interaction with inner belt protons, therefore, can be addressed using quasi-linear diffusion codes, which allows faster exploration of parameter space.

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