College of Sciences and Mathematics: Recent submissions
Now showing items 101-120 of 399
Natural arsenic contamination of Holocene alluvial aquifers by linked tectonic, weathering, and microbial processes
(2022-10-26)
Linked tectonic, geochemical, and biologic processes lead to natural arsenic contamination of groundwater in Holocene alluvial aquifers, which are the main threat to human health around the world. These groundwaters are ...
Evolution of CIR storm on 22 July 2009
(2022-10-25)
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, ...
Simulation of pressure pulses in the bow shock and magnetosheath driven by variations in interplanetary magnetic field direction
(2022-10-25)
Two-dimensional (2-D) hybrid simulations are carried out to study the effects of the variation in the interplanetary magnetic field (IMF) direction on the bow shock, magnetosheath, and magnetosphere. A curvilinear coordinate ...
An 40Ar/39Ar thermochronology of the Ofoten-Troms region: Implications for terrane amalgamation and extensional collapse of the northern Scandinavian Caledonides
(2022-10-25)
Fifteen Ar-40/Ar-39 cooling ages are reported for metamorphic hornblende and muscovite from far traveled terranes constituting the Ofoten nappe stack of northern Norway. Eight cooling ages on hornblende range from 425 to ...
Reactive transport of trace elements and isotopes in the Eutaw coastal plain aquifer, Alabama
(2022-10-25)
We integrate groundwater geochemistry, mineralogy, and numerical modeling techniques to study the reactive transport of heavy metals and isotopes in the Eutaw coastal plain aquifer, Alabama. Geochemical data show that the ...
EUV emissions from solar wind charge exchange in the Earth's magnetosheath: Three-dimensional global hybrid simulation
(2022-10-25)
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 ...
Generation of dynamic pressure pulses downstream of the bow shock by variations in the interplanetary magnetic field orientation
(2022-10-25)
One-dimensional resistive MHD and hybrid simulations are carried out to study the manner by which variations of the interplanetary magnetic field (IMF) direction generate dynamic pressure pulses in the magnetosheath. The ...
Hybrid simulation of foreshock waves and ion spectra and their linkage to cusp energetic ions
(2022-10-25)
A three-dimensional global hybrid simulation is carried out to investigate energetic ions and electromagnetic waves in the quasi-parallel (Q-∥) bow shock and cusp for a typical interplanetary magnetic field configuration ...
Hybrid simulation of foreshock waves and ion spectra and their linkage to cusp energetic ions
(2022-10-25)
A three-dimensional global hybrid simulation is carried out to investigate energetic ions and electromagnetic waves in the quasi-parallel (Q-parallel to) bow shock and cusp for a typical interplanetary magnetic field ...
Re-Reconnection Processes of Magnetopause Flux Ropes: Three-Dimensional Global Hybrid Simulations
(2022-10-18)
Magnetopause flux ropes (FRs) play a crucial role in the transport of energy and plasma from the solar wind to the Earth's magnetosphere. Once formed by multiple X-line reconnection, the FRs move poleward, during which ...
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 ...