Article
Astronomy & Astrophysics
S. M. Shaaban, M. Lazar, R. F. Wimmer-Schweingruber, H. Fichtner
Summary: The study of instability in solar-wind plasma reveals that proton firehose modes can grow under certain conditions and explain observational results. The presence of suprathermal Kappa-distributed populations further enhances this instability, making it more effective.
ASTROPHYSICAL JOURNAL
(2021)
Article
Physics, Multidisciplinary
S. Sultana
Summary: This study investigates the formation and propagation nature of ion-acoustic shock waves in a magnetized plasma with superthermal trapped electrons using fluid dynamical approach for the first time. It examines the basic features of these shock waves and their dependence on plasma parameters, and discusses the potential applications in space and laboratory plasma environments with nonthermal trapped electrons.
CHINESE JOURNAL OF PHYSICS
(2021)
Article
Physics, Fluids & Plasmas
Z. J. Guo, H. B. Zhuo, H. L. Fan, M. Q. Li, S. Z. Wu, T. W. Huang, H. Zhang, C. T. Zhou
Summary: The fluid nonlinearities of driven ion acoustic waves (IAWs) in superthermal electron plasmas are investigated by fluid theory and one-dimensional fluid simulation. The presence of superthermal electrons leads to stronger harmonic generation and larger nonlinear frequency shifts of IAWs. Simulation results also verify the accuracy of a simple three-wave fluid theory in predicting the growth rate and threshold of the IAW decay instability.
PHYSICS OF PLASMAS
(2023)
Article
Physics, Fluids & Plasmas
Lunan Liu, R. Ochoukov, K. G. McClements, R. O. Dendy, V Bobkov, M. Weiland, R. Bilato, H. Faugel, D. Moseev, M. Salewski, W. Zhang, Xinjun Zhang, Yubao Zhu, B. Chapman, A. Zalzali
Summary: Bursts of ion cyclotron emission (ICE) in helium plasmas heated by sub-Alfvenic beam-injected hydrogen ions in the ASDEX Upgrade tokamak are caused by magnetoacoustic cyclotron instability (MCI), which is sensitive to the energy and velocity distribution of the injected ions and is suppressed by the slowing down of the dominant beam-injected ion velocity and the spreading of the fast ion distribution profile. The time evolution of MCI growth rates is consistent with measured ICE amplitudes, helping to explain the disappearance of ICE signals after NBI turn-off much faster than the slowing down times of the beam ions.
Article
Physics, Multidisciplinary
Pablo S. Moya, Roberto E. Navarro
Summary: Research using quasilinear kinetic theory has shown that turbulent magnetic power can drive protons in space plasma to undergo transverse heating, leading to an increase in temperature anisotropy and a decrease in parallel proton beta. This may explain why constituents of the solar wind can be observed far from thermodynamic equilibrium and close to instability thresholds.
FRONTIERS IN PHYSICS
(2021)
Article
Physics, Fluids & Plasmas
Haozhe Kong, Huasheng Xie, Jizhong Sun
Summary: This study systematically investigates the influence of key parameters on Ion Cyclotron Emission (ICE) and provides several novel results. The impact of parallel velocity spread on the bandwidth and continuous spectrum of ICE excited by super-Alfvenic fast ions is examined, as well as the influence of perpendicular velocity spread on the growth rate of Magnetoacoustic Cyclotron Instability (MCI). The relationship between MCI growth rate and the square root of the number density ratio is found to transition to a linear relationship as the velocity spread increases. Additionally, the study reveals that high harmonics are more sensitive to changes in propagation angle and that the growth rate at high harmonics increases significantly for both sub-Alfvenic and greatly sub-Alfvenic fast ions.
Article
Astronomy & Astrophysics
Qi Zhu, Xing Cao, Binbin Ni, Xudong Gu, Xin Ma
Summary: This study investigates the effects of hot protons on the scattering loss of ring current protons induced by electromagnetic ion cyclotron (EMIC) waves, by calculating the proton bounce-averaged pitch angle diffusion coefficients. The results show that inclusion of hot protons significantly decreases the diffusion coefficients of low-energy protons, while increasing the scattering efficiency of high-energy protons at certain angles. The cold plasma approximation underestimates the loss timescales of low-energy protons but overestimates that of high-energy protons. The differences in proton loss timescales caused by hot protons depend on the hot proton concentration, temperature anisotropy, and L-shell.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2022)
Article
Physics, Multidisciplinary
Suresh Basnet, Anish Maskey, Atit Deuja, Raju Khanal
Summary: The effects of ion beam current on dust charge fluctuations and ion acoustic wave propagation were studied, showing that increasing negative ion concentration decreases the instability of ion waves and shifts the dust surface potential into the positive domain. Additionally, when electrons are significantly depleted, the plasma shifts into an ion-ion plasma state, causing ion waves to exhibit a damping phenomenon.
Article
Astronomy & Astrophysics
Alexander Shane, Michael Liemohn
Summary: The study investigates the conditions for the energization process of high-energy superthermal electrons on the dayside crustal magnetic fields at Mars. By calculating characteristic energy profiles and wave parameters, it was found that wave-particle interactions are more efficient than Coulomb collisions in modifying the pitch angle distribution of electrons.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2021)
Article
Physics, Multidisciplinary
Erzhong Li, X. L. Zou, L. Q. Xu, Y. Q. Chu, X. Feng, H. Lian, H. Q. Liu, A. D. Liu, M. K. Han, J. Q. Dong, H. H. Wang, J. W. Liu, Q. Zang, S. X. Wang, T. F. Zhou, Y. H. Huang, L. Q. Hu, C. Zhou, H. X. Qu, Y. Chen, S. Y. Lin, B. Zhang, J. P. Qian, J. S. Hu, G. S. Xu, J. L. Chen, K. Lu, F. K. Liu, Y. T. Song, J. G. Li, X. Z. Gong
Summary: Experimental achievement of high-beta steady-state long pulse plasmas with steep central electron temperature gradient is reported. Turbulent current, driven by electron temperature gradient mode (ETG), is observed and can reach a significant ratio of the bootstrap current. The maximum values of turbulent current and electron temperature gradient lead to the destabilization of an m/n=1/1 kink mode.
PHYSICAL REVIEW LETTERS
(2022)
Article
Astronomy & Astrophysics
Yun Yan, Chao Yue, Ze-Fan Yin, Xu-Zhi Zhou, Qiu-Gang Zong, Jing-Huan Li
Summary: Large-amplitude electromagnetic ion cyclotron (EMIC) waves can rapidly deplete >1 MeV electrons, with the amplitude-dependent properties and excitation mechanisms revealed through statistical analysis of Van Allen Probe B observations. These large-amplitude EMIC waves are more likely to occur in the afternoon-dusk sector in the northern hemisphere, with left-hand polarization and smaller wave normal angles. The generation of higher-amplitude EMIC waves is favored by high proton beta parallel conditions and is influenced by both substorm activity and solar wind dynamic pressure.
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2023)
Article
Multidisciplinary Sciences
Masafumi Shoji, Yoshizumi Miyoshi, Lynn M. Kistler, Kazushi Asamura, Ayako Matsuoka, Yasumasa Kasaba, Shoya Matsuda, Yoshiya Kasahara, Iku Shinohara
Summary: A study using Arase data provides the first observational evidence that the frequency drift of electromagnetic ion cyclotron (EMIC) waves is caused by cyclotron trapping. By analyzing wave data observed by Arase from March 2017 to September 2019, researchers found the best falling tone emission event and showed direct evidence of the formation of a proton hill.
SCIENTIFIC REPORTS
(2021)
Article
Physics, Fluids & Plasmas
Jiangyue Han, Zhe Gao, S. K. Hansen
Summary: Parametric decay instabilities near the upper hybrid resonance layer are investigated using a 1D framework. The kinetic nonlinear dispersion relation of the instabilities is numerically calculated for parameters corresponding to electron cyclotron heating experiments at the ASDEX-U tokamak. The forward scattering processes driven by X-mode and linearly converted electron Bernstein waves (EBWs) lead to a primary instability where the pump waves decay into lower hybrid waves and sideband EBWs. A frequency shift of 930 MHz is observed for the sideband EBWs.
PHYSICS OF PLASMAS
(2023)
Article
Geosciences, Multidisciplinary
MingHui Zhu, YiQun Yu, Xing Cao, BinBin Ni, XingBin Tian, JinBin Cao, Vania K. Jordanova
Summary: This study investigates the effects of polarization-reversed EMIC waves on the dynamics of the ring current and proton precipitation loss. The results show that the polarization reversal can decrease the scattering rates of protons and slightly affect the global ring current intensity and proton precipitation.
EARTH AND PLANETARY PHYSICS
(2022)
Article
Astronomy & Astrophysics
Hamid Reza Pakzad, Davod Nobahar
Summary: This research uses the pseudopotential method to study the properties of dust-ion-acoustic (DIA) solitons in an unmagnetized dusty plasma. An important finding is that DIA solitons exist beyond certain critical values of the electron-to-ion density ratio and the superthermal parameter of electrons. The study results contribute to a better understanding of the behavior of dust-ion waves in various spaces.
Article
Physics, Fluids & Plasmas
Manfred A. Hellberg, Frank Verheest, Richard L. Mace
PHYSICS OF PLASMAS
(2018)
Article
Computer Science, Interdisciplinary Applications
S. Dalena, P. Chuychai, R. L. Mace, A. Greco, G. Qin, W. H. Matthaeus
COMPUTER PHYSICS COMMUNICATIONS
(2012)
Article
Computer Science, Interdisciplinary Applications
R. F. Abdul, R. L. Mace
COMPUTER PHYSICS COMMUNICATIONS
(2014)
Article
Astronomy & Astrophysics
F. D. Henning, R. L. Mace, S. R. Pillay
JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS
(2011)
Article
Physics, Fluids & Plasmas
G. M. Webb, R. L. Mace
JOURNAL OF PLASMA PHYSICS
(2015)
Article
Physics, Fluids & Plasmas
S. Dalena, A. Greco, A. F. Rappazzo, R. L. Mace, W. H. Matthaeus
Article
Physics, Fluids & Plasmas
R. L. Mace, S. Dalena, W. H. Matthaeus
PHYSICS OF PLASMAS
(2012)
Article
Physics, Fluids & Plasmas
F. Nsengiyumva, R. L. Mace, M. A. Hellberg
PHYSICS OF PLASMAS
(2013)
Article
Physics, Fluids & Plasmas
F. D. Henning, R. L. Mace
PHYSICS OF PLASMAS
(2014)
Article
Physics, Fluids & Plasmas
F. Nsengiyumva, M. A. Hellberg, F. Verheest, R. L. Mace
PHYSICS OF PLASMAS
(2014)
Article
Physics, Fluids & Plasmas
R. L. Mace
PHYSICS OF PLASMAS
(2018)
Article
Physics, Fluids & Plasmas
R. F. Abdul, A. P. Matthews, R. L. Mace
Summary: This study investigates the electron temperature anisotropy driven whistler instability using bi-kappa velocity distribution. The results show that the Maxwellian electron run has the fastest growth rate, while the kappa e = 2 case exhibits the slowest growth rate.
PHYSICS OF PLASMAS
(2021)
Article
Physics, Fluids & Plasmas
R. F. Abdul, R. L. Mace
PHYSICS OF PLASMAS
(2015)
Article
Physics, Fluids & Plasmas
F. Nsengiyumva, M. A. Hellberg, R. L. Mace
PHYSICS OF PLASMAS
(2015)