Article
Geosciences, Multidisciplinary
B. Grison, O. Santolik, J. Lukacevic, M. E. Usanova
Summary: Studies have shown that EMIC waves in the outer magnetosphere are most frequently observed in the vicinity of the magnetopause, especially at distances less than two Earth radii. Additionally, there is a noted local time asymmetry in EMIC occurrence rates.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Astronomy & Astrophysics
Ruoxian Zhou, Binbin Ni, Song Fu, Shangchun Teng, Xin Tao, Zejun Hu, Jianguang Guo, Man Hua, Juan Yi, YingJie Guo, Luhuai Jiao, Xin Ma, Xudong Gu
Summary: This study provides a detailed survey of concurrent Electromagnetic ion cyclotron (EMIC) waves and Magnetosonic (MS) waves using Van Allen Probes observations. The results indicate that most of the concurrent EMIC waves and MS waves are H+ band waves and that specific geomagnetic conditions favor their occurrence. Additionally, the study suggests that stronger MS waves are more likely to occur than EMIC waves during moderate and active geomagnetic times.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2022)
Article
Geosciences, Multidisciplinary
L. W. Blum, A. Koval, I. G. Richardson, L. B. Wilson, D. Malaspina, A. Greeley, A. N. Jaynes
Summary: A sequence of discrete solar wind structures within the sheath region of an interplanetary coronal mass ejection on November 6, 2015 caused compressions and releases in the dayside magnetosphere, leading to phenomena like electromagnetic ion cyclotron wave bursts. This event highlights the importance of fine-scale solar wind structure, particularly in complex sheath regions, in driving dayside phenomena within the inner magnetosphere.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Physics, Fluids & Plasmas
Jiansheng Yao, Yingkui Zhao, Yi Li, Lihui Chai, Jicheng Sun
Summary: This paper proposes a new excitation mechanism for the H e + band EMIC wave, showing that the frequency and temperature of the H + band EMIC wave triggered by anisotropic hot H + changes significantly, followed by the excitation of a narrow H e + band EMIC wave. Further investigation reveals that the X-type distribution of H e + may be caused by pitch angle scattering from the H + band EMIC wave, which in turn stimulates the H e + band EMIC wave. The free energy to excite the H e + band EMIC wave is found to come from higher energy H e + with a butterfly wing shaped part of X type distribution.
PHYSICS OF PLASMAS
(2021)
Article
Geosciences, Multidisciplinary
L. Capannolo, W. Li, H. Spence, A. T. Johnson, M. Shumko, J. Sample, D. Klumpar
Summary: By analyzing coordinated multisatellite observations, this study found that electron precipitation driven by EMIC waves occurs in a broad region near dusk, mostly confined to 3.5-7.5 L-shells, with each precipitation event occurring on localized radial scales. The data from FIREBIRD-II suggest that EMIC waves can efficiently scatter electron energies from around 200 to 300 keV up to the expected MeV energies.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Mechanics
Yair De-Leon, Chaim I. Garfinkel, Nathan Paldor
Summary: Analytical and numerical solutions of the eigenvalue equation associated with zonally propagating waves of the linearized rotating shallow water equations are derived in a channel on the equatorial beta-plane in the presence of a uniform mean zonal flow. The mean state causes the dispersion curves of each of the free Rossby and Poincare waves to nearly coalesce in pairs of modes when the zonal wavenumber increases. The eigenvalue problem loses its Sturm-Liouville structure for large mean speed and large zonal wavenumber, and the eigenfunctions have multiple extrema between successive zeros of the function itself.
Article
Geosciences, Multidisciplinary
Zhiqiang Wang, Lingwei Zhang, Jiacheng Zhong
Summary: This study investigates the electromagnetic ion cyclotron (EMIC) instabilities in the inner magnetosphere, considering the effect of temperature anisotropic electrons. The results show that perpendicular anisotropic electrons have an inhibiting effect on EMIC instabilities, while parallel anisotropic electrons may have a promoting or inhibiting effect depending on the direction of wave group velocity. The study also reveals the coupling between electron firehose modes and EMIC modes, and the generation of secondary waves near the ion cyclotron frequencies. The findings highlight the importance of hot anisotropic electrons as an energy provider for EMIC modes, which has been overlooked in previous studies. Additionally, the study reports the existence of a backward EMIC wave with opposite group velocity.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Astronomy & Astrophysics
Ning Kang, Quanming Lu, Xinliang Gao, Xueyi Wang, Huayue Chen, Shui Wang
Summary: EMIC waves are a common plasma wave in the Earth's inner magnetosphere, playing a crucial role in particle dynamics in the radiation belt and ring current. This study uses a 2D hybrid simulation to investigate the propagation of EMIC waves and proposes a novel method for diagnosing the wave normal angle, as well as analyzing the polarization change of the waves with propagation direction.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2021)
Article
Geosciences, Multidisciplinary
S. Teng, N. Liu, Q. Ma, X. Tao, W. Li
Summary: This study demonstrates that ring-like proton distributions can generate both magnetosonic (MS) waves and electromagnetic ion cyclotron (EMIC) waves, providing direct observational evidence for previous theoretical predictions. By comparing linear growth rates and proton distribution evolution, the study reveals the generation mechanisms and relationship between these waves.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Astronomy & Astrophysics
B. Remya, A. J. Halford, D. G. Sibeck, K. R. Murphy, M. -c. Fok
Summary: Geomagnetic indices are used to study the occurrence of electromagnetic ion cyclotron (EMIC) waves under different geomagnetic conditions. However, the drivers of EMIC waves vary during non-storm, storm time and individual storm phases. Using data from the twin Van Allen Probes over 7 years, it is shown that the occurrence probability of EMIC waves is best represented by considering individual storm phases rather than a specific geomagnetic activity index. The occurrence rates of EMIC waves during different storm phases vary significantly, even for a given geomagnetic index.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
Article
Astronomy & Astrophysics
M. Fraz Bashir, Anton Artemyev, Xiao-Jia Zhang, Vassilis Angelopoulos
Summary: Energetic electron losses in the Earth's inner magnetosphere are dominated by outward radial diffusion and scattering into the atmosphere by various electromagnetic waves. This study aims to examine the effects of nonlinear resonances and hot plasma dispersion on wave-particle resonant interaction resulting in electron scattering. The results highlight the importance of nonlinear effects for simulations of energetic electron fluxes in the inner magnetosphere.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2022)
Article
Mechanics
Weaam Alhejaili, Ismat Naeem, W. Masood, Sherif M. E. Ismaeel, S. A. El-Tantawy
Summary: The nonlinear equations governing tripolar vortices (TPVs) in an inhomogeneous magnetoplasma with inertialess non-Maxwellian electrons are investigated. Analytical and numerical solutions are obtained for various cases, and the dispersion relation for drift ion-acoustic waves (IAWs) and the condition for shear flow instability are derived. It is found that the size and formation of TPVs are modified by the presence of non-Maxwellian electrons in three different distributions. The interplay between low and high-energy electrons with spiky distribution is discussed, along with its novel effects on vortex propagation.
Article
Geosciences, Multidisciplinary
I. P. Pakhotin, I. R. Mann, D. Sydorenko, R. Rankin
Summary: The Swarm mission observed in situ conjugate electromagnetic ion cyclotron (EMIC) waves with a complex and unusual pattern of energy distribution. These waves exhibit a peak at mid-latitudes near the source and a secondary peak at a lower L-value. A wave propagation model suggests that the secondary peak may be explained by wave power redirection due to resonance, resulting in interference with EMIC waves propagating from the opposite hemisphere.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Astronomy & Astrophysics
Taifeng Jin, Li Lei, Yiteng Zhang, Lianghai Xie, Fuhao Qiao
Summary: By statistically analyzing the mirror-mode structures in the Martian magnetosheath observed by Mars Atmosphere and Volatile Evolution from 2015 to 2018, it is found that these structures mainly occur near the bow shock and have various shapes such as peak-like, wave-like, and dip-like. The mirror-mode structures quickly saturate after their formation and remain in a nonlinear saturation state driven by the magnetosheath flow. However, the dayside magnetosheath of Mars is unstable, preventing the mirror-mode structures from fully evolving into the decaying phase.
ASTROPHYSICAL JOURNAL
(2022)
Article
Geosciences, Multidisciplinary
Nigang Liu, Yuyue Jin, Zhaoguo He, Jiang Yu, Kun Li, Jun Cui
Summary: In this study, the impact of solar wind on plasmaspheric hiss and EMIC waves was investigated using observational data. It was found that high-density solar wind leads to the excitation of these waves, while solar wind decompression results in their rapid disappearance. These findings provide new insights into the Earth's space weather and solar wind-magnetosphere coupling.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Geosciences, Multidisciplinary
Hui Zhu, Zhenpeng Su, Fuliang Xiao, Huinan Zheng, Yuming Wang, Chao Shen, Tao Xian, Shui Wang, C. A. Kletzing, W. S. Kurth, G. B. Hospodarsky, H. E. Spence, G. D. Reeves, H. O. Funsten, J. B. Blake, D. N. Baker
GEOPHYSICAL RESEARCH LETTERS
(2015)
Article
Geosciences, Multidisciplinary
Zhenpeng Su, Hui Zhu, Fuliang Xiao, Huinan Zheng, Yuming Wang, Chao Shen, Min Zhang, Shui Wang, C. A. Kletzing, W. S. Kurth, G. B. Hospodarsky, H. E. Spence, G. D. Reeves, H. O. Funsten, J. B. Blake, D. N. Baker, J. R. Wygant
GEOPHYSICAL RESEARCH LETTERS
(2015)
Article
Geosciences, Multidisciplinary
Fuliang Xiao, Qinghua Zhou, Yihua He, Chang Yang, Si Liu, D. N. Baker, H. E. Spence, G. D. Reeves, H. O. Funsten, J. B. Blake
GEOPHYSICAL RESEARCH LETTERS
(2015)
Article
Multidisciplinary Sciences
Zhenpeng Su, Hui Zhu, Fuliang Xiao, Q. -G. Zong, X. -Z. Zhou, Huinan Zheng, Yuming Wang, Shui Wang, Y. -X. Hao, Zhonglei Gao, Zhaoguo He, D. N. Baker, H. E. Spence, G. D. Reeves, J. B. Blake, J. R. Wygant
NATURE COMMUNICATIONS
(2015)
Article
Multidisciplinary Sciences
Fuliang Xiao, Chang Yang, Zhenpeng Su, Qinghua Zhou, Zhaoguo He, Yihua He, D. N. Baker, H. E. Spence, H. O. Funsten, J. B. Blake
NATURE COMMUNICATIONS
(2015)
Article
Geosciences, Multidisciplinary
Fuliang Xiao, Qinghua Zhou, Zhenpeng Su, Zhaoguo He, Chang Yang, Si Liu, Yihua He, Zhonglei Gao
GEOPHYSICAL RESEARCH LETTERS
(2016)
Article
Geosciences, Multidisciplinary
Zhonglei Gao, Zhenpeng Su, Hui Zhu, Fuliang Xiao, Huinan Zheng, Yuming Wang, Chao Shen, Shui Wang
GEOPHYSICAL RESEARCH LETTERS
(2016)
Article
Geosciences, Multidisciplinary
Chang Yang, Zhenpeng Su, Fuliang Xiao, Huinan Zheng, Yuming Wang, Shui Wang, H. E. Spence, G. D. Reeves, D. N. Baker, J. B. Blake, H. O. Funsten
GEOPHYSICAL RESEARCH LETTERS
(2016)
Article
Engineering, Multidisciplinary
Yang QiWu, Yang Chang, He YiHua, Liu Si, Zhou QingHua, Xiao FuLiang
SCIENCE CHINA-TECHNOLOGICAL SCIENCES
(2016)
Article
Astronomy & Astrophysics
Qinghua Zhou, Fuliang Xiao, Chang Yang, Si Liu, Yihua He, J. R. Wygant, D. N. Baker, H. E. Spence, G. D. Reeves, H. O. Funsten
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2016)
Article
Geosciences, Multidisciplinary
Qinghua Zhou, Fuliang Xiao, Chang Yang, Si Liu, Yihua He, D. N. Baker, H. E. Spence, G. D. Reeves, H. O. Funsten
GEOPHYSICAL RESEARCH LETTERS
(2017)
Article
Geosciences, Multidisciplinary
Chang Yang, Zhenpeng Su, Fuliang Xiao, Huinan Zheng, Yuming Wang, Shui Wang, H. E. Spence, G. D. Reeves, D. N. Baker, J. B. Blake, H. O. Funsten
GEOPHYSICAL RESEARCH LETTERS
(2017)
Article
Astronomy & Astrophysics
Fuliang Xiao, Si Liu, Xin Tao, Zhenpeng Su, Qinghua Zhou, Chang Yang, Zhaoguo He, Yihua He, Zhonglei Gao, D. N. Baker, H. E. Spence, G. D. Reeves, H. O. Funsten, J. B. Blake
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2017)
Article
Geosciences, Multidisciplinary
Chang Yang, Fuliang Xiao, Yihua He, Si Liu, Qinghua Zhou, Mingyue Guo, Wanli Zhao
GEOPHYSICAL RESEARCH LETTERS
(2018)
Article
Geosciences, Multidisciplinary
Si Liu, Qi Yan, Chang Yang, Qinghua Zhou, Zhaoguo He, Yihua He, Zhonglei Gao, Fuliang Xiao
GEOPHYSICAL RESEARCH LETTERS
(2018)