SM13G-05
Modulation of chorus wave intensity by ULF waves from Van Allen Probes Observation
Monday, 14 December 2015: 14:40
2018 (Moscone West)
Lunjin Chen, University of Texas at Dallas, Richardson, TX, United States, Zhiyang Xia, University of Texas at Dallas, Dallas, TX, United States and Lei Dai, NSSC National Space Science Center, CAS, Beijing, China
Abstract:
We present an observation event from Van Allen Probes measurement, showing the modulation of chorus wave intensity by ULF waves. Detailed properties of ULF waves are examined and the waves appear to be the strong coupling between second harmonic poloidal mode and mirror mode. ULF waves have a period of ~ 1 min while quasi-parallel chorus waves have frequency range from a few 100 Hz to above 1 kHz. Chorus wave intensity is enhanced at the region where the field aligned component Bz of ULF wave is antiparallel to the background magnetic field, and vice verse. We also show the potential mechanism responsible for the modulation. The question of such modulation itself is interesting and, what is more, its implication is broad in magnetospheric physics, especially dynamics of radiation belt and ring current.
