SM21A-2467
Statistical Features of EMIC Waves Observed on Van Allen Probes in the Inner Magnetosphere
Tuesday, 15 December 2015
Poster Hall (Moscone South)
Dae-Young Lee1, Sung-Jun Roh2, Junghee Cho2, Dae-Kyu Shin1, Junga Hwang3, Kyung-Chan Kim3, William S Kurth4, Craig Kletzing4, John R Wygant5 and Scott A Thaller5, (1)Chungbuk National University, Cheongju, South Korea, (2)Chungbuk National University, Department of Astronomy and Space Science, Cheongju, South Korea, (3)KASI Korea Astronomy and Space Science Institute, Daejeon, South Korea, (4)University of Iowa, Iowa City, IA, United States, (5)University of Minnesota Twin Cities, Minneapolis, MN, United States
Abstract:
Electromagnetic ion cyclotron (EMIC) waves are one of the key plasma waves that can affect charged particle dynamics in the Earth’s inner magnetosphere. Knowledge of global distribution of the EMIC waves is critical for accurately assessing the significance of its interaction with charged particles. With the Van Allen Probes EMFISIS observations, we have surveyed EMIC events for ~2.5 years period. We have identified well-defined, banded wave activities only, as distinguished from broad band wave activities. We have obtained global distribution of occurrence of the identified waves with distinction between H- and He-bands. We compare it with previous observations such as THEMIS and CRRES. For the identified events we have drawn all the basic wave properties including wave frequency, polarization, wave normal angle. In addition, we have distinguished the EMIC events that occur inside the plasmasphere and at the plasmapause from those outside the plasmasphere. Finally, we have tested solar wind and geomagnetic dependence of the wave events. We give discussions about implications of these observations on wave generation mechanism and interaction with radiation belt electrons.
