In situ evidence of the modification of the parallel propagation of EMIC waves by heated He+ ions. Issue 7 (28th July 2016)

• Record Type: Journal Article
• Authors: Yuan, Zhigang; Yu, Xiongdong; Wang, Dedong; Huang, Shiyong; Li, Haimeng; Yu, Tao; Qiao, Zheng; Wygant, John R.; Funsten, Herbert O.
• Is Part Of: Journal of geophysical research. Volume 121:Issue 7(2016:Jul.)
• Page Start: 6711
• Page End: 6717
• Publication Date: 2016-07-28
• Subjects: EMIC waves -- He+ ion heating -- stop band -- Van Allen Probes -- ring current ions; Magnetospheric physics -- Periodicals; Space environment -- Periodicals; Cosmic physics -- Periodicals; Planets -- Atmospheres -- Periodicals; Heliosphere (Astrophysics) -- Periodicals; Geophysics -- Periodicals; 523.01
• DOI: 10.1002/2016JA022573
• Languages: English
• ISSNs: 2169-9380

Abstract

Abstract: With observations of the Van Allen Probe B, we report in situ evidence of the modification of the parallel propagating electromagnetic ion cyclotron (EMIC) waves by heated He + ions. In the outer boundary of the plasmasphere, accompanied with the He + ion heating, the frequency bands of H + and He + for EMIC waves merged into each other, leading to the disappearance of a usual stop band between the gyrofrequency of He + ions (ΩHe+ ) and the H + cutoff frequency ( ω H+co ) in the cold plasma. Moreover, the dispersion relation for EMIC waves theoretically calculated with the observed plasma parameters also demonstrates that EMIC waves can indeed parallel propagate across ΩHe+ . Therefore, the paper provides an in situ evidence of the modification of the parallel propagation of EMIC waves by heated He + ions. Key Points: In situ evidence of modification of parallel propagating EMIC waves by heated H + ions Characteristics of modified parallel propagating EMIC waves Wave‐particle interaction between EMIC waves and cold H + ions