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Scalings for the Alfven-cyclotron instability: Linear dispersion theory and hybrid particle-in-cell simulations 

Gary, S. Peter; Fu, Xiangrong; Cowee, Misa M.; Winske, Dan; Liu, Kaijun; 0000-0001-5882-1328 (2020-06-01)
The Alfven-cyclotron instability is driven by an ion temperature anisotropy such that T-perpendicular to/T-|| >1 where and || denote directions perpendicular and parallel to a uniform background magnetic field B-o, ...

Scalings of Alfven-cyclotron and ion Bernstein instabilities on temperature anisotropy of a ring-like velocity distribution in the inner magnetosphere 

Min, Kyungguk; Liu, Kaijun; Gary, S. Peter; 0000-0002-2095-8529; 0000-0001-5882-1328 (2020-06-03)
A ring-like proton velocity distribution with f(p)(v)/v>0 and which is sufficiently anisotropic can excite two distinct types of growing modes in the inner magnetosphere: ion Bernstein instabilities with multiple ion ...

Signatures of electron Landau resonant interactions with chorus waves from THEMIS observations 

Min, Kyungguk; Liu, Kaijun; Li, Wen; 0000-0002-2095-8529; 0000-0001-5882-1328 (2020-06-05)
Simultaneous observations of electron phase space density (PSD) and chorus waves for more than 4 years by the Time History of Events and Macroscale Interactions during Substorms (THEMIS) are analyzed to identify signatures ...

Simulation studies of a recorder in three dimensions 

Giordano, Nicholas J. (2015-10-12)
The aeroacoustics of a recorder are explored using a direct numerical simulation based on the Navier–Stokes equations in three dimensions. The qualitative behavior is studied using spatial maps of the air pressure and ...

Solar cycle variation of plasma mass density in the outer magnetosphere: Magnetoseismic analysis of toroidal standing Alfven waves detected by Geotail 

Takahashi, Kazue; Denton, Richard E.; Hirahara, Masafumi; Min, Kyungguk; Ohtani, Shin-ichi; Sanchez, Ennio; 0000-0002-2095-8529 (2020-06-05)
We study the variation of plasma mass density in the outer magnetosphere over a solar cycle using mass density estimated from the frequency of fundamental toroidal standing Alfven waves observed by the Geotail spacecraft. ...

Solitary potential structures associated with ion and electron beams near 1 R-E altitude 

Bounds, SR; Pfaff, Rf; Knowlton, SF; Mozer, FS; Temerin, MA; Kletzing, CA (2020-06-30)
Small-scale solitary electric potential structures are commonly observed on auroral field lines with the Polar Electric Field Instrument (EFI). This study focuses on observations of solitary structures in the southern ...

Spectral properties and associated plasma energization by magnetosonic waves in the Earth's magnetosphere: Particle-in-cell simulations 

Sun, Jicheng; Gao, Xinliang; Lu, Quanming; Chen, Lunjin; Liu, Xu; Wang, Xueyi; Tao, Xin; Wang, Shui; 0000-0001-5533-5981 (2020-06-01)
In this paper, we perform a 1-D particle-in-cell (PIC) simulation model consisting of three species, cold electrons, cold ions, and energetic ion ring, to investigate spectral structures of magnetosonic waves excited by ...

Statistical correlation of low-altitude ENA emissions with geomagnetic activity from IMAGE/MENA observations 

Mackler, D. A.; Jahn, J-M; Perez, J. D.; Pollock, C. J.; Valek, P. W. (2020-06-03)
Plasma sheet particles transported Earthward during times of active magnetospheric convection can interact with exospheric/thermospheric neutrals through charge exchange. The resulting Energetic Neutral Atoms (ENAs) are ...

Study of EMIC wave excitation using direct ion measurements 

Min, Kyungguk; Liu, Kaijun; Wygant, John R.; 0000-0002-2095-8529; 0000-0001-5882-1328 (2020-06-05)
With data from Van Allen Probes, we investigate electromagnetic ion cyclotron (EMIC) wave excitation using simultaneously observed ion distributions. Strong He band waves occurred while the spacecraft was moving through ...

A study of the electromagnetic proton cyclotron instability as a generation mechanism for EMIC waves in the Earth's magnetosphere using SCATHA data 

Nguyen, Son T.; Perez, J. D.; Fennell, Joseph F. (2020-06-16)
Using 59 days of magnetic field data from SCATHA, a study of the electromagnetic proton cyclotron instability as a generation mechanism for EMIC waves in the Earth's magnetosphere has been conducted. From 1181 events found, ...

Test-Particle Simulations of Linear and Nonlinear Interactions Between a 2-D Whistler-Mode Wave Packet and Radiation Belt Electrons 

da Silva, C. L.; Denton, R. E.; Hudson, M. K.; Millan, R. M.; Liu, K.; Bortnik, J. (2020-05-27)
Using test-particle simulations, we describe (in 2-D) the interaction of an ensemble of electrons with a discrete whistler-mode wave packet, which propagates with a moderate wave-normal angle with respect to the background ...

Three-dimensional global hybrid simulation of dayside dynamics associated with the quasi-parallel bow shock 

Lin, Y.; Wang, XY; 0000-0001-8003-9252; 0000-0001-5533-5981 (2020-06-18)
A three-dimensional global-scale hybrid simulation is carried out, for the first time, for dynamics of the dayside bow shock-magnetosphere system associated with the quasi-parallel bow shock. A case with IMF along the ...

Three-dimensional hybrid simulation of magnetosheath reconnection under northward and southward interplanetary magnetic field 

Pang, Y.; Lin, Y.; Deng, X. H.; Wang, X. Y.; Tan, B.; 0000-0001-8003-9252; 0000-0001-5533-5981 (2020-06-16)
A three-dimensional (3-D) global hybrid simulation is carried out for the generation and structure of magnetic reconnection in the magnetosheath because of the interaction of an interplanetary tangential discontinuity (TD) ...

Three-dimensional MHD simulations of interplanetary rotational discontinuities impacting the Earth's bow shock and magnetosheath 

Cable, S.; Lin, Y.; 0000-0001-8003-9252 (2020-06-30)
The first ever fully three-dimensional magnetohydrodynamic (MHD) simulations of the detailed effects of MHD discontinuities on the magnetosheath have been performed. The simulation results predict that the interaction ...

Trapped and precipitating protons in the inner magnetosphere as seen by IMAGE 

Perez, JD; Zhang, XX; Brandt, PC; Mitchell, DG; Jahn, JM; Pollock, CJ; Mende, SB (2020-06-18)
[1] Images from the IMAGE satellite of precipitating protons (SU12/FUV) and trapped protons at 8.5 (MENA) and 33 keV (HENA) are compared during three periods: ( 1) 12 August 2000 from 1000 UT to 1145 UT just after the peak ...

TWINS stereoscopic imaging of multiple peaks in the ring current 

Perez, J. D.; Goldstein, J.; McComas, D. J.; Valek, P.; Buzulukova, N.; Fok, M. -C.; Singer, H. J. (2020-06-05)
Global, ion equatorial flux distributions and energy spectra are presented from stereoscopic Two Wide-Angle Imaging Neutral-Atom Spectrometers (TWINS) 1 and TWINS 2 energetic neutral atom (ENA) images for two time periods, ...

Two-Dimensional gcPIC Simulation of Rising-Tone Chorus Waves in a Dipole Magnetic Field 

Lu, Quanming; Ke, Yangguang; Wang, Xueyi; Liu, Kaijun; Gao, Xinliang; Chens, Lunjin; Wang, Shui (2020-05-26)
Rising-tone chorus waves have already been successfully produced in a mirror magnetic field with the use of one- and two-dimensional particle-in-cell (PIC) simulations. However, in reality, the background magnetic field ...

Two-dimensional global hybrid simulation of pressure evolution and waves in the magnetosheath 

Lin, Y; Denton, RE; Lee, LC; Chao, JK; 0000-0001-8003-9252 (2020-06-30)
A two-dimensional hybrid simulation is carried out for the global structure of the magnetosheath. Quasi-perpendicular magnetosonic/fast mode waves with large-amplitude in-phase oscillations of the magnetic field and the ...

Two-dimensional hybrid simulation of the dayside reconnection layer and associated ion transport 

Xie, H.; Lin, Y.; 0000-0001-8003-9252 (2020-06-30)
The structure of the reconnection layer at the dayside magnetopause is studied by using a two-dimensional (2-D) hybrid code. The simulation domain is a rectangle in the at plane around an X line at the magnetopause. In our ...

Two-Dimensional Particle-in-Cell Simulation of Magnetosonic Wave Excitation in a Dipole Magnetic Field 

Chen, Lunjin; Sun, Jicheng; Lu, Quanming; Wang, Xueyi; Gao, Xinliang; Wang, Dedong; Wang, Shui (2020-05-27)
The excitation of magnetosonic waves in the meridian plane of a rescaled dipole magnetic field is investigated, for the first time, using a general curvilinear particle-in-cell simulation. Our simulation demonstrates that ...