SM21A-2466
Kinetic Alfvén Waves in the Inner Magnetosphere Triggered by an Interplanetary Shock
Tuesday, 15 December 2015
Poster Hall (Moscone South)
David Malaspina1, Seth G Claudepierre2, Kazue Takahashi3, Allison N Jaynes4, Scot Richard Elkington1, Robert Ergun1, John R Wygant5, Geoffrey D Reeves6 and Craig Kletzing7, (1)University of Colorado, Boulder, Laboratory for Atmospheric and Space Physics, Boulder, CO, United States, (2)Aerospace Corporation, Los Angeles, CA, United States, (3)Johns Hopkins University, Applied Physics Laboratory, Laurel, MD, United States, (4)University of Colorado at Boulder, LASP, Boulder, CO, United States, (5)University of Minnesota, School of Physics and Astronomy, Minneapolis, MN, United States, (6)Los Alamos National Laboratory, Los Alamos, NM, United States, (7)University of Iowa, Physics and Astronomy, Iowa City, IA, United States
Abstract:
An interplanetary shock impacted Earth's magnetic field on October 2, 2013, compressing the magnetosphere and triggering a global 3.5 mHz oscillation. This large-amplitude ULF (ultra low frequency) wave was observed in-situ, using both magnetic and electric field data, by the Van Allen Probe B spacecraft. At the same time, Van Allen Probe B observed higher frequency broadband wave power in conjunction with, and modulated by, this ULF wave. A detailed analysis reveals that these broadband waves are kinetic Alfvén waves, possibly generated by large-scale Alfvénic fluctuations coupling to smaller scales. This event suggests that magnetospheric compression by interplanetary shocks can induce abrupt generation of kinetic Alfvén waves over large portions of the inner magnetosphere, potentially resulting in prompt ion heating throughout the inner magnetosphere.
