Japan Geoscience Union Meeting 2016

Presentation information

International Session (Oral)

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

[P-EM08] Inner magnetosphere: Latest results and new perspectives

Mon. May 23, 2016 3:30 PM - 5:00 PM 103 (1F)

Convener:*Danny Summers(Memorial University of Newfoundland), Yusuke Ebihara(Research Institute for Sustainable Humanosphere, Kyoto University), Yoshizumi Miyoshi(Institute for Space-Earth Environmental Research, Nagoya University), Chair:Yoshizumi Miyoshi(Institute for Space-Earth Environmental Research, Nagoya University)

4:45 PM - 5:00 PM

[PEM08-16] Limitation of energetic ring current ion spectra

*Danny Summers1, Run Shi1 (1.Dept of Math and Stats,Memorial University of Newfoundland)

Keywords:ring current ion spectra, EMIC waves, limiting ion spectrum

We address the problem of determining the limiting energetic ring current ion spectrum resulting from electromagnetic ion cyclotron (EMIC)-wave-ion-interactions. We solve the problem in a relativistic regime, incorporating a cold background multi-ion plasma component and without assuming a predetermined form for the energy distribution. The limiting spectrum is determined by the condition that the EMIC waves acquire a specified gain over a given convective length scale for all frequencies over which wave growth occurs. We find that the limiting ion spectrum satisfies an integral equation that must be solved numerically. However,at large particle energy E, the limiting spectrum takes the simple form J ~ 1/E . Moreover,this 1/E spectral shape does not depend on the energetic ion in question nor on the background multi-ion plasma composition. We provide numerical solutions for the limiting spectra for Earth-like parameters. In addition, at Earth and four other planets we compare measured ion spectra with corresponding numerical limiting spectra.