A simulation study of RX-mode waves generation in the equatorial plasmasphere

نوع مقاله : مقاله پژوهشی‌

نویسندگان

1 Institute of Geophysics, University of Tehran, Tehran

2 Department of Geophysics, Graduate School of Science, Tohoku University, Sendai, Japan

چکیده

The generation mechanism of RX-mode waves in the equatorial plasmasphere has not been well understood. The Akebono passing through the storm time geomagnetic equator shows the possibility of the local enhancement of RX-mode waves in association with intense Z-mode waves in the equatorial region. We use the initial parameters inferred from observational data from around the plasma-wave generation region obtained by the Akebono satellite. A comparison of linear growth-rate calculations and simulation results is presented. The results of the simulation show two strong peaks related to the Z-mode and RX-mode waves, while the separation of these wave frequencies is equal to one cyclotron frequency. It is shown that electromagnetic Z- and RX-mode waves could be coupled by a nonlinear interaction.

کلیدواژه‌ها


عنوان مقاله [English]

A simulation study of RX-mode waves generation in the equatorial plasmasphere

نویسندگان [English]

  • Mohammad Javad Kalaee 1
  • Yuto Katoh 2
چکیده [English]

The generation mechanism of RX-mode waves in the equatorial plasmasphere has not been well understood. The Akebono passing through the storm time geomagnetic equator shows the possibility of the local enhancement of RX-mode waves in association with intense Z-mode waves in the equatorial region. We use the initial parameters inferred from observational data from around the plasma-wave generation region obtained by the Akebono satellite. A comparison of linear growth-rate calculations and simulation results is presented. The results of the simulation show two strong peaks related to the Z-mode and RX-mode waves, while the separation of these wave frequencies is equal to one cyclotron frequency. It is shown that electromagnetic Z- and RX-mode waves could be coupled by a nonlinear interaction.

کلیدواژه‌ها [English]

  • RX- mode
  • Simulation
  • cyclotron frequency
  • growth rate
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