College of Sciences and Mathematics: Recent submissions
Now showing items 101-120 of 389
Physics of Wind Musical Instruments
(2022-10-14)
This project involves simulations of wind musical instruments for NSF project PHY-1806231. The archived codes were developed as part of the project with NSF support. Details of the dataset are described in the file ...
Generation of rising-tone chorus in a two-dimensional mirror field by using the general curvilinear PIC code
(2022-10-12)
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 ...
Fine structure of low-energy H+ in the nightside auroral region
(2022-10-12)
Low-energy H+ data with 6-s resolution from the retarding ion mass spectrometer instrument on DE 1 have been analyzed to reveal the fine structure at middle altitudes of the nightside auroral region. A new method for ...
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 ...
BAM files associated with Macaca arctoides hybridization analysis
(2022-10-12)
Genital divergence is thought to contribute to reproductive barriers by establishing a “lock-and-key" mechanism for reproductive compatibility. One such example, Macaca arctoides, the bear macaque, has compensatory changes ...
Gap Formation Around 0.5 Omega(e) in the Whistler-Mode Waves Due To the Plateau-Like Shape in the Parallel Electron Distribution: 2D PIC Simulations
(2022-10-12)
The power gap around 0.5 Omega(e) (where Omega(e) is the equatorial electron gyrofrequency) of whistler-mode waves is commonly observed in the Earth's inner magnetosphere, but its generation mechanism is still under debate. ...
Magnetic Reconnection Inside Solar Wind Rotational Discontinuity During Its Interaction With the Quasi-Perpendicular Bow Shock and Magnetosheath
(2022-10-12)
Using a three-dimensional global hybrid simulation, we investigate the formation and evolution of ion-scale magnetic reconnection inside an interplanetary rotational discontinuity (RD) owing to its interaction with the ...
Wave Normal Angle Distribution of Magnetosonic Waves in the Earth's Magnetosphere: 2-D PIC Simulation
(2022-10-11)
Radiation belt electrons can be accelerated and scattered by magnetosonic waves in the Earth's magnetosphere, and the scattering rate of electrons is sensitive to the wave normal angle. However, observationally it is ...
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 ...
Laser Ar-40/Ar-39 age constraints on Miocene sequences from the Bengal basin: Implications for middle Miocene denudation of the eastern Himalayas
(2022-10-10)
Petrographic, mineral-chemistry and subsurface studies reveal that orogenic sedimentation had already begun in the Bengal basin by the early Miocene. Laser Ar-40/Ar-39 age determinations were made for detrital muscovite ...
TRANSIENT SCATTERING FROM DIELECTRIC CYLINDERS - E-FIELD, H-FIELD, AND COMBINED FIELD SOLUTIONS
(2022-10-05)
In this work, the problem of transient scattering by arbitrarily shaped two-dimensional dielectric cylinders is solved using the marching-on-in-time technique. The dielectric problem is approached via the equivalence ...
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 ...
A study of the electromagnetic proton cyclotron instability as a generation mechanism for EMIC waves in the Earth's magnetosphere using SCATHA data
(2022-10-04)
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, ...
Signatures of electron Landau resonant interactions with chorus waves from THEMIS observations
(2022-10-04)
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 ...
Ion Bernstein instability dependence on the proton-to-electron mass ratio: Linear dispersion theory
(2022-10-04)
Fast magnetosonic waves, which have as their source ion Bernstein instabilities driven by tenuous ring-like proton velocity distributions, are frequently observed in the inner magnetosphere. One major difficulty in the ...
Multi-Event Studies of Sudden Energetic Electron Enhancements in the Inner Magnetosphere and Its Association With Plasmapause Positions
(2022-10-04)
Sudden enhancements of energetic electrons (tens of keV to <500 keV) at low L-shells have been frequently observed by Van Allen Probes. It is, however, still unclear how deep these electrons can reach and what the responsible ...
Modeling the loss of inner belt protons by magnetic field line curvature scattering
(2022-09-30)
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 ...
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 ...
Investigation of storm timemagnetotail and ion injection using three-dimensional global hybrid simulation
(2022-09-29)
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 ...
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 ...