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 ...
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 ...
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 ...
Multi-Event Study on the Connection Between Subauroral Polarization Streams and Deep Energetic Particle Injections in the Inner Magnetosphere
(2023-01-25)
Energetic electron flux enhancements for 100s keV energies are often observed at low L shells (L < 4) in the inner magnetosphere during geomagnetic storms. However, protons with similar energies do not penetrate as deeply ...
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 ...
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 ...
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 ...
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 ...
Foreshock wave interaction with the magnetopause: Signatures of mode conversion
(2022-09-30)
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 ...
Fast Magnetosonic Waves Observed by Van Allen Probes: Testing Local Wave Excitation Mechanism
(2022-12-01)
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 ...
Particle-in-Cell Simulations of the Fast Magnetosonic Mode in a Dipole Magnetic Field: 1-D Along the Radial Direction
(2020-05-28)
An electromagnetic particle-in-cell code is used to investigate self-consistent evolution of the fast magnetosonic mode in a one-dimensional configuration along the radial direction in a dipole background magnetic field. ...
Proton velocity ring-driven instabilities and their dependence on the ring speed: Linear theory
(2022-10-12)
Linear dispersion theory is used to study the Alfven-cyclotron, mirror and ion Bernstein instabilities driven by a tenuous (1%) warm proton ring velocity distribution with a ring speed, v(r), varying between 2v(A) and ...
LOW-ALTITUDE OBSERVATIONS AND MODELING OF QUASI-STEADY MAGNETOPAUSE RECONNECTION
(2022-09-29)
Data from two near-conjugate passes of DE 1 and DE 2 through the cusp/cleft region of the Earth's magnetosphere are presented and compared with model calculations of particle transport from the solar wind to spacecraft ...
Effect of continued nitrogen enrichment on greenhouse gas emissions from a wetland ecosystem in the Sanjiang Plain, Northeast China: A 5 year nitrogen addition experiment
(2023-01-25)
Mounting evidence supports that wetland ecosystems, one of the largest carbon pools on the earth, are exposed to ample nitrogen (N) additions due to atmospheric deposition or N loading from upstream agricultural fertilizer ...
SIMULATION STUDY OF THE RIEMANN PROBLEM ASSOCIATED WITH THE MAGNETOTAIL RECONNECTION
(2022-10-11)
The structure of reconnection layer in the distant magnetotail is studied by solving the Riemann problem for the evolution of an initial current sheet using one-dimensional MHD and hybrid simulations. Initially, the current ...
Solitary potential structures associated with ion and electron beams near 1 R-E altitude
(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 ...
Statistical correlation of low-altitude ENA emissions with geomagnetic activity from IMAGE/MENA observations
(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 ...
Lattice thermal conductivity of MgO at conditions of Earth's interior
(2020-06-29)
Thermal conductivity of the Earth’s lower mantle greatly impacts the mantle convection style and affects the heat conduction from the core to the mantle. Direct laboratory measurement of thermal conductivity of mantle ...