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Equatorial Evolution of the Fast Magnetosonic Mode in the Source Region: Observation-Simulation Comparison of the Preferential Propagation Direction 

Min, Kyungguk; Boardsen, Scott A.; Denton, Richard E.; Liu, Kaijun; 0000-0001-5882-1328 (2020-05-28)
Recent analysis of an event observed by the Van Allen Probes in the source region outside the plasmapause has shown that fast magnetosonic waves (also referred to as equatorial noise) propagate preferentially in the azimuthal ...

EUV emissions from solar wind charge exchange in the Earth's magnetosheath: Three-dimensional global hybrid simulation 

He, Fei; Zhang, Xiao-Xin; Wang, Xueyi; Chen, Bo; 0000-0001-5533-5981 (2020-06-05)
In this paper, a three-dimensional (3-D) global hybrid simulation code and a 3-D geocoronal hydrogen model are used to systematically study the extreme ultraviolet (EUV) emissions at 30.4nm produced by solar wind charge ...

Evolution of CIR storm on 22 July 2009 

Perez, J. D.; Grimes, E. W.; Goldstein, J.; McComas, D. J.; Valek, P.; Billor, N. (2020-06-09)
Global images of ion intensities are deconvolved from TWINS ENA images during the main and recovery phase of a CIR storm on 22 July 2009. The global spatial ion images taken at different times, along with solar wind data, ...

Evolution of low-altitude and ring current ENA emissions from a moderate magnetospheric storm: Continuous and simultaneous TWINS observations 

Valek, P.; Brandt, P. C.; Buzulukova, N.; Fok, M-C.; Goldstein, J.; McComas, D. J.; Perez, J. D.; Roelof, E.; Skoug, R. (2020-06-12)
The moderate storm of 22 July 2009 is the largest measured during the extended solar minimum between December 2006 and March 2010. We present observations of this storm made by the two wide-angle imaging neutral-atom ...

Experimental characterization of broadband electrostatic noise due to plasma compression 

DuBois, Ami M.; Thomas, Edward Jr.; Amatucci, William E.; Ganguli, Gurudas; 0000-0003-0947-8038; 0000-0002-7747-0284 (2020-06-05)
For a wide variety of laboratory and space plasma environments, theoretical predictions state that plasmas are unstable to inhomogeneous flows over a very broad frequency range. Such sheared flows are generated in the ...

Explaining the Railsback stretch in terms of the inharmonicity of piano tones and sensory dissonance 

Giordano, Nicholas J. (2015-10-26)
The perceptual results of Plomp and Levelt for the sensory dissonance of a pair of pure tones are used to estimate the dissonance of pairs of piano tones. By using the spectra of tones measured for a real piano, the effect ...

Externally driven plasmaspheric ULF waves observed by the Van Allen Probes 

Takashashi, Kazue; Min, Kyungguk; MacDowall, Robert; 0000-0002-2095-8529 (2020-06-05)
We analyze data acquired by the Van Allen Probes on 8 November 2012, during a period of extended low geomagnetic activity, to gain new insight into plasmaspheric ultralow frequency (ULF) waves. The waves exhibited strong ...

Fast magnetosonic waves driven by shell velocity distributions 

Min, Kyungguk; Liu, Kaijun; 0000-0002-2095-8529; 0000-0001-5882-1328 (2020-06-05)
Using linear dispersion theory and particle-in-cell simulations, we explore the ion Bernstein instability driven by the shell-type ion velocity distribution which is related to the excitation of fast magnetosonic waves in ...

Fast Magnetosonic Waves Observed by Van Allen Probes: Testing Local Wave Excitation Mechanism 

Min, Kyungguk; Liu, Kaijun; Wang, Xueyi; Chen, Lunjin; Denton, Richard E.; 0000-0001-5882-1328; 0000-0001-5533-5981 (2020-05-28)
Linear Vlasov theory and particle-in-cell (PIC) simulations for electromagnetic fluctuations in a homogeneous, magnetized, and collisionless plasma are used to investigate a fast magnetosonic wave event observed by the Van ...

Field line distribution of mass density at geostationary orbit 

Denton, R. E.; Takahashi, Kazue; Lee, Jimyoung; Zeitler, C. K.; Wimer, N. T.; Litscher, L. E.; Singer, H. J.; Min, Kyungguk; 0000-0002-2095-8529 (2020-06-05)
The distribution of mass density along the field lines affects the ratios of toroidal (azimuthally oscillating) Alfven frequencies, and given the ratios of these frequencies, we can get information about that distribution. ...

Foreshock wave interaction with the magnetopause: Signatures of mode conversion 

Shi, Feng; Cheng, Lei; Lin, Yu; Wang, Xueyi; 0000-0001-8003-9252; 0000-0001-5533-5981 (2020-06-01)
Our previous hybrid simulation (Shi et al., 2013) under a radial interplanetary magnetic field (IMF) and a supercritical solar wind Mach number has shown that foreshock compressional waves originated from the quasi-parallel ...

Free-Boundary Axisymmetric MHD Equilibrium 

Guazzotto, Luca (2018-07-09)
The calculation of equilibrium conditions is a common task in the study and modeling of magnetic-confinement experiments for con- trolled nuclear fusion, in which a high-temperature plasma is confined in a finite region ...

Generation of anomalous flows near the bow shock by its interaction with interplanetary discontinuities 

Lin, Yu; 0000-0001-8003-9252 (2020-06-30)
Two-dimensional hybrid simulations using a curvilinear coordinate system are carried out to study the interaction of the Earth's bow shock (BS) with an interplanetary directional discontinuity. In particular, plasma flow ...

Generation of near-Earth reconnection by divergent flows in the plasma sheet 

Lin, Y.; Swift, DW; 0000-0001-8003-9252 (2020-06-25)
A global two-dimensional hybrid simulation is carried out to study the evolution of the near-Earth plasma sheet. It is shown that reconnection X lines and plasmoids can be generated by diverging flows in the plasma sheet. ...

Generation of rising-tone chorus in a two-dimensional mirror field by using the general curvilinear PIC code 

Ke, Yangguang; Gao, Xinliang; Lu, Quanming; Wang, Xueyi; Wang, Shui; 0000-0001-5533-5981 (2020-05-29)
Recently, the generation of rising-tone chorus has been implemented with one-dimensional (1-D) particle-in-cell (PIC) simulations in an inhomogeneous background magnetic field, where both the propagation of waves and motion ...

Global hybrid simulation of mode conversion at the dayside magnetopause 

Shi, Feng; Lin, Yu; Wang, Xueyi; 0000-0001-8003-9252; 0000-0001-5533-5981 (2020-06-05)
Mode conversion at the magnetopause has been suggested to lead to the generation of kinetic Alfven waves (KAWs) and effective mass transport from the solar wind into the magnetosphere. To investigate the mode conversion ...

Global hybrid simulation of the dayside reconnection layer and associated field-aligned currents 

Lin, Y.; 0000-0001-8003-9252 (2020-06-26)
A two-dimensional global hybrid simulation is carried out to study the structure of the magnetopause boundary layer in the noon-midnight meridian plane associated with the dayside reconnection. In the simulation the bow ...

Global images of trapped ring current ions during main phase of 17 March 2015 geomagnetic storm as observed by TWINS 

Perez, J. D.; Goldstein, J.; McComas, D. J.; Valek, P.; Fok, M-C; Hwang, Kyoung-Joo (2020-06-03)
A unique view of the trapped particles in the inner magnetosphere provided by energetic neutral atom (ENA) imaging is used to observe the dynamics of the spatial structure and the pitch angle anisotropy on a global scale ...

Global observations of ring current dynamics during corotating interaction region-driven geomagnetic storms in 2008 

Grimes, E. W.; Perez, J. D.; Goldstein, J.; McComas, D. J.; Valek, P. (2020-06-12)
We examine the evolution of the ring current during the main and early recovery phases of three geomagnetic storms driven by corotating interaction regions. The equatorial energy density profiles of 5-30 keV ions are ...

Global patterns of Joule heating in the high-latitude ionosphere 

Zhang, XX; Wang, C.; Chen, T.; Wang, YL; Tan, A; Wu, TS; Germany, GA; Wang, W (2020-06-18)
[1] A compiled empirical global Joule heating (CEJH) model is described in this study. This model can be used to study Joule heating patterns, Joule heating power, potential drop, and polar potential size in the high-latitude ...