Modeling electromagnetic ion cyclotron waves in the inner magnetosphere (Invited)
Thursday, 4 September 2014: 11:00 AM
Regency Ballroom (Hyatt Regency)
Lunjin Chen, University of Texas at Dallas, Richardson, TX, United States, Vania Jordanova, Los Alamos National Laboratory, Los Alamos, NM, United States and Richard M Thorne, UCLA, Los Angeles, CA, United States
Abstract:
Electromagnetic ion cyclotron (EMIC) waves play important roles as intermediaries in the interplay between various plasma populations in the magnetosphere, including the plasmasphere, ring current, and radiation belts. We use combined Ring Current-Atmospheric Ring Current Model, Self-Consistent Magnetic Field Model and Ray Tracing Model to model global propagation characteristics and spectral characteristics of EMIC waves. The combined model is applied for the June 2001 geomagnetic storm and the model results are compared and shown to be consistent with the in-situ wave measurement/proxy from multiple geosynchronous satellites. The modeling results are also shown to be consistent with images of proton aurora at subauroral latitudes observed by the IMAGE satellite. We will also present the effect of warm He+ and hot H+, which affect significantly EMIC wave generation near He+ gyrofrequency and might lead to vanishing of âstop bandâ in the cold plasma, and the effect of fine-density structures, which tend to keep wave vector more field-aligned and thus lead to enhanced amplification of EMIC waves. Finally, the questions on quantifying the contributions of EMIC waves to radiation belt electron loss will be discussed.
