Physics: Recent submissions
Now showing items 141-160 of 192
Comparison of TWINS and THEMIS observations of proton pitch angle distributions in the ring current during the 29 May 2010 geomagnetic storm
(2020-06-09)
The first comparison between energy-dependent ion pitch angle distributions in the ring current deconvolved from Two Wide-angle Imagining Neutral-atom Spectrometers (TWINS) energetic neutral atom (ENA) images and measured ...
Global hybrid simulation of mode conversion at the dayside magnetopause
(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 ...
Field line distribution of mass density at geostationary orbit
(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. ...
Quiet time equatorial mass density distribution derived from AMPTE/CCE and GOES using the magnetoseismology technique
(2020-06-05)
An inversion technique for estimating the properties of the magnetospheric plasma from the harmonic frequencies of the toroidal standing Alfven waves has been used to derive the global equatorial mass density covering ...
Experimental characterization of broadband electrostatic noise due to plasma compression
(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 ...
Modeling the loss of inner belt protons by magnetic field line curvature scattering
(2020-06-05)
The sudden loss of energetic protons in the inner radiation belt has been observed during geomagnetic storms. It is hypothesized that this sudden loss occurs because of changes in the geomagnetic field configuration which ...
Signatures of electron Landau resonant interactions with chorus waves from THEMIS observations
(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 ...
Investigation of storm time magnetotail and ion injection using three-dimensional global hybrid simulation
(2020-06-05)
Dynamics of the near-Earth magnetotail associated with substorms during a period of extended southward interplanetary magnetic field is studied using a three-dimensional (3-D) global hybrid simulation model that includes ...
The Comprehensive Inner Magnetosphere-Ionosphere Model
(2020-06-05)
Simulation studies of the Earth's radiation belts and ring current are very useful in understanding the acceleration, transport, and loss of energetic particles. Recently, the Comprehensive Ring Current Model (CRCM) and ...
Solar cycle variation of plasma mass density in the outer magnetosphere: Magnetoseismic analysis of toroidal standing Alfven waves detected by Geotail
(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. ...
Whistler anisotropy instabilities as the source of banded chorus: Van Allen Probes observations and particle-in-cell simulations
(2020-06-05)
Magnetospheric banded chorus is enhanced whistler waves with frequencies (r)<(e), where (e) is the electron cyclotron frequency, and a characteristic spectral gap at (r)similar or equal to(e)/2. This paper uses spacecraft ...
Externally driven plasmaspheric ULF waves observed by the Van Allen Probes
(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 ...
TWINS stereoscopic imaging of multiple peaks in the ring current
(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, ...
EUV emissions from solar wind charge exchange in the Earth's magnetosheath: Three-dimensional global hybrid simulation
(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 ...
One- and two-dimensional hybrid simulations of whistler mode waves in a dipole field
(2020-06-05)
We simulate whistler mode waves using a hybrid code. There are four species in the simulations, hot electrons initialized with a bi-Maxwellian distribution with temperature in the direction perpendicular to background ...
Study of EMIC wave excitation using direct ion measurements
(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 ...
Fast magnetosonic waves driven by shell velocity distributions
(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 ...
Dipolarization fronts as earthward propagating flux ropes: A three-dimensional global hybrid simulation
(2020-06-03)
Dipolarization fronts (DFs) as earthward propagating flux ropes (FRs) in the Earth's magnetotail are presented and investigated with a three-dimensional (3-D) global hybrid simulation for the first time. In the simulation, ...
Regime transition of ion Bernstein instability driven by ion shell velocity distributions
(2020-06-03)
Linear kinetic dispersion theory is used to investigate a regime transition of the ion Bernstein instability driven by a proton velocity distribution with positive slopes with respect to the perpendicular velocity, ...
Proton velocity ring-driven instabilities in the inner magnetosphere: Linear theory and particle-in-cell simulations
(2020-06-03)
Linear dispersion theory and electromagnetic particle-in-cell (PIC) simulations are used to investigate linear growth and nonlinear saturation of the proton velocity ring-driven instabilities, namely, ion Bernstein instability ...