Browsing Physics by Issue Date
Now showing items 1-20 of 193
Simulation studies of a recorder in three dimensions
(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 ...
Explaining the Railsback stretch in terms of the inharmonicity of piano tones and sensory dissonance
(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 ...
Oxygen-hydrogen differentiated observations from TWINS: The 22 July 2009 storm
(2020-06-09)
The 22 July 2009 magnetic storm is the first significant storm during the emergence of the recent prolonged solar cycle minimum. This moderate storm (minimum Dst approximately -78 nT) has received a good deal of attention ...
Overlap of the plasmasphere and ring current: Relation to subauroral ionospheric heating
(2020-06-18)
The overlap of the ring current with the outer plasmasphere is thought to play a major role in storm-time related increases in the subauroral ambient topside electron temperature. Instabilities generated within the overlap ...
Global-scale hybrid simulation of cusp precipitating ions associated with magnetopause reconnection under southward IMF
(2022-09-20)
With a 3-D global-scale hybrid simulation model, we investigate the energy spectra of cusp precipitating ions and issues associated with magnetopause reconnection under a southward IMF. Both the spatial and temporal energy ...
Three-dimensional MHD simulations of interplanetary rotational discontinuities impacting the Earth's bow shock and magnetosheath
(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 ...
Kinetic Alfven waves in three-dimensional magnetic reconnection
(2022-10-27)
Alfvenic waves are believed to be fundamentally important in magnetic reconnection. Kinetic dynamics of particles can break the Alfven speed limit in the evolution and propagation of perturbations during reconnection. In ...
VHF and UHF Electromagnetic Radiation Produced by Streamers in Lightning
(2020-03-10)
In this letter, we report simulation results of streamer propagation and collision that produce electromagnetic radiation in the very high frequency (VHF) and ultra high frequency (UHF) bands. The streamers are initiated ...
Reversal of magnetic field rotation in the reconnection layer due to shear flow effects
(2022-09-29)
We investigate the effects of shear flows on the so-called component reconnection, in which the guide field B-y not equal 0, by solving a one-dimensional Riemann problem for magnetopause reconnection using a resistive MHD ...
Pickup proton instabilities and scattering in the distant solar wind and the outer heliosheath: Hybrid simulations
(2022-10-27)
The growth of magnetic field fluctuations driven by the injection of pickup ions perpendicular to a background magnetic field in a homogeneous, collisionless plasma is studied using one-dimensional hybrid simulations. ...
Equatorial Pitch Angle Distributions of 1-50 keV Electrons in Earth's Inner Magnetosphere: An Empirical Model Based on the Van Allen Probes Observations
(2023-01-19)
Using 7 years of data from the Helium, Oxygen, Proton, and Electron instrument on the Van Allen Probes, equatorial pitch angle distributions (PADs) of 1-50 keV electrons in Earth's inner magnetosphere are investigated ...
Global observations of ring current dynamics during corotating interaction region-driven geomagnetic storms in 2008
(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 ...
Scalings of Alfven-cyclotron and ion Bernstein instabilities on temperature anisotropy of a ring-like velocity distribution in the inner magnetosphere
(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 ...
Effect of IMF B-y on the Entry of Solar Wind Ions Into the Near-Earth Tail Lobe: Global Hybrid Simulation and MMS Observation
(2022-11-08)
Global simulations predict that the low-latitude mantle may be an important pathway for the solar wind entry into the tail magnetosphere close to the current sheet when interplanetary magnetic field (IMF) B-y dominates ...
The Hall Electric Field in Earth's Magnetotail Thin Current Sheet
(2020-05-28)
One of the most important properties of Earth's magnetotail thin current sheet (TCS) is that its current is predominantly contributed by magnetized electrons. The Hall electric field, normal to the TCS and generated by ...
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 ...
Generation of near-Earth reconnection by divergent flows in the plasma sheet
(2022-10-04)
[1] 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 ...
Spectral properties and associated plasma energization by magnetosonic waves in the Earth's magnetosphere: Particle-in-cell simulations
(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 ...
The NSF/DOE Partnership in Basic Plasma Science & Engineering at 20: Report on the Anniversary Workshop
(2019-11-11)
A workshop recognizing the 20th anniversary of the NSF/DOE Partnership in Basic Plasma Science and Engineering was held at NSF on January 9-11, 2017. The workshop demonstrated some of the remarkable research and broader ...
Magnetosheath Reconnection Before Magnetopause Reconnection Driven by Interplanetary Tangential Discontinuity: A Three-Dimensional Global Hybrid Simulation With Oblique Interplanetary Magnetic Field
(2020-05-28)
Terrestrial dayside dynamics associated with a southward turning, oblique interplanetary magnetic field (IMF) carried by an interplanetary tangential discontinuity (TD) is investigated by performing a three-dimensional ...