Japan Geoscience Union Meeting 2022

Presentation information

[E] Oral

P (Space and Planetary Sciences ) » P-EM Solar-Terrestrial Sciences, Space Electromagnetism & Space Environment

[P-EM11] Dynamics of the Inner Magnetospheric System

Wed. May 25, 2022 10:45 AM - 12:15 PM 303 (International Conference Hall, Makuhari Messe)

convener:Kunihiro Keika(Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo ), convener:Yoshizumi Miyoshi(Institute for Space-Earth Environmental Research, Nagoya University), Lauren W Blum(University of Colorado Boulder), convener:Yuri Shprits(Helmholtz Centre Potsdam GFZ German Research Centre for Geosciences), Chairperson:Yikai Hsieh(Reserach Institute for Sustainable Humanosphere, Kyoto University), Kunihiro Keika(Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo)


12:00 PM - 12:15 PM

[PEM11-11] Cross-energy coupling between magnetosonic waves to electromagnetic ion cyclotron waves through cold ion heating

*Kazushi Asamura1, Masafumi Shoji2, Yoshizumi Miyoshi2, Yoshiya Kasahara3, Yasumasa Kasaba4, Atsushi Kumamoto4, Fuminori Tsuchiya4, Shoya Matsuda3, Ayako Matsuoka5, Mariko Teramoto6, Yoichi Kazama7, Iku Shinohara1 (1.Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 2.ISEE, Nagoya University, 3.Graduate school of natural science and technology, Kanazawa university , 4.Graduate school of science, Tohoku University , 5.Graduate school of science, Kyoto University , 6.Graduate school of engineering, Kyushu Institute of Technology, 7.Institute of Astronomy and Astrophysics, Academia Sinica, Taiwan)

Keywords:Magnetosonic waves, Electromagnetic ion cyclotron waves, Ion heating, Wave - particle interaction analysis

Fast magnetosonic waves (MSWs) are commonly observed in the equatorial inner magnetosphere. Past numerical simulations show that MSWs can accelerate low-energy ions through cyclotron resonance, although the observational evidence is still unclear. The Arase satellite found an event of perpendicular heating of low-energy protons simultaneously with enhancement of MSWs. Using the wave-particle interaction analysis (WPIA), we obtain direct evidence of energy transfer from the observed MSWs to the low-energy (26 – 725 eV) protons. We found these protons give their energies to electro-magnetic ion cyclotron (EMIC) waves with frequencies just below the local proton cyclotron frequency. Since MSW is excited by a ring-like distribution of ions, this analysis suggests that a part of energies of the ring current ions is transferred to the low-energy ions through excitation and damping of MSWs in the inner magnetosphere, and then, a part of the transferred energies is spent to excite high-frequency EMIC waves.