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Finite Different Time-Domain Simulation Of Terahertz Waves Propagation Through Unmagnetized Plasma, Aditha Srikantha Senarath
Finite Different Time-Domain Simulation Of Terahertz Waves Propagation Through Unmagnetized Plasma, Aditha Srikantha Senarath
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In order to support ongoing terahertz time-domain spectroscopic experiments involving plasma characterization, it is beneficial to simulate the interaction of THz pulses with varying plasma configurations. In this approach, a 1-D Finite Difference Time Domain (FDTD) model was constructed to simulate the interaction of terahertz radiation with a plasma medium. In order to incorporate the plasma properties into the simulation, a Z-transformation was applied. This model is capable of simulating the following properties of plasmas including electron density, collision frequency, and the interaction length of the plasma medium. The simulated model was characterized using terahertz time-domain spectroscopy. The effects of …
Evolution Of Electron Properties After Nanosecond Repetitively Pulsed Discharges In Air Measured By Thomson Scattering, Chase S. Murray
Evolution Of Electron Properties After Nanosecond Repetitively Pulsed Discharges In Air Measured By Thomson Scattering, Chase S. Murray
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This work was an investigation of nanosecond repetitively pulsed discharges in air by measuring the evolution of electron density and electron temperature between pulses using Thomson scattering of laser light. Bursts of repetitive pulses within several microseconds after the initial pulse were found to exhibit a coupling effect and create an even higher electron density than the initial pulse. The wide range of temperatures and densities of the electrons existing between pulses allow an opportunity to explore both the collective and non-collective regimes of Thomson scattering. By measuring electron density and temperature at a variety of times, an accurate description …
One-Dimensional Kinetic Particle-In-Cell Simulations Of Various Plasma Distributions, Richard N. Vanderburgh
One-Dimensional Kinetic Particle-In-Cell Simulations Of Various Plasma Distributions, Richard N. Vanderburgh
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A one-dimensional kinetic particle-in-cell (PIC) MATLAB simulation was created to demonstrate the time-evolution of various plasma distributions. Building on previous plasma PIC programs written in FORTRAN and Python, this work recreates the computational and diagnostic tools of these packages in a more user- and educational-friendly development environment. Plasma quantities such as plasma frequency and species charge-mass ratios are arbitrarily defined. A one-dimensional spatial environment is defined by total length and number and size of spatial grid points. In the first time-step, charged particles are given initial positions and velocities on a spatial grid. After initialization, the program solves for the …
A Parallel Spectral Method Approach To Model Plasma Instabilities, Kevin S. Scheiman
A Parallel Spectral Method Approach To Model Plasma Instabilities, Kevin S. Scheiman
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The study of solar-terrestrial plasma is concerned with processes in magnetospheric, ionospheric, and cosmic-ray physics involving different particle species and even particles of different energy within a single species. Instabilities in space plasmas and the earth's atmosphere are driven by a multitude of free energy sources such as velocity shear, gravity, temperature anisotropy, electron, and, ion beams and currents. Microinstabilities such as Rayleigh-Taylor and Kelvin-Helmholtz instabilities are important for the understanding of plasma dynamics in presence of magnetic field and velocity shear. Modeling these turbulences is a computationally demanding processes; requiring large memory and suffer from excessively long runtimes. Previous …