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Full-Text Articles in Physical Processes
Scaling Laws For Diffusion In Crystallized Plasma From Molecular Dynamics, Dany Yaacoub
Scaling Laws For Diffusion In Crystallized Plasma From Molecular Dynamics, Dany Yaacoub
Theses and Dissertations
Diffusion coefficients for crystallized Coulomb plasmas are essential microphysics input for modeling white dwarf cores and neutron star crusts. Solving for diffusion coefficients require running large molecular dynamics simulations with thousands of particles over millions of timesteps. The diffusion in a crystallized plasma has been largely ignored and is often taken to be zero in stellar evolution codes. We find that not only is this incorrect, but we find that the diffusion in a crystallized plasma can be modeled completely using a universal scaling law independent of screening. Our simulations also show that the dominant mode of diffusion in a …
Comet Nuclei Activity Simulation Using Percolation Theory On Comet 67p/Churyumov– Gerasimenko, Ahmad Sohani
Comet Nuclei Activity Simulation Using Percolation Theory On Comet 67p/Churyumov– Gerasimenko, Ahmad Sohani
Theses and Dissertations
Comets, remnants of the solar system's formation, exhibits partially unexplained outbursts that are closely tied to the physical structure of the nucleus. To investigate outbursts, we employed pore network modeling techniques, such as the Bower-Watson algorithm and Voronoi diagrams, to better represent the nucleus' complex porous structure and simulate gas transfer processes. We examined heat diffusion in the comet's subsurface and its influence on crystallization. The extra heat generated by crystallization can shift the crystalline front deeper into the nucleus, accelerating subsurface evaporation rates. This process results in the formation of a thicker ice mantle with reduced porosity on the …
Ensemble Forecasting Of Coronal Mass Ejections Using The Wsa-Enlil With Coned Model, Daniel J. Emmons Ii
Ensemble Forecasting Of Coronal Mass Ejections Using The Wsa-Enlil With Coned Model, Daniel J. Emmons Ii
Theses and Dissertations
The combination of the Wang-Sheeley-Arge (WSA) coronal model, ENLIL heliospherical model version 2.7, and Coned Model version 1.3 (WSA-ENLIL with Coned Model) was employed to form ensemble forecasts for 15 halo coronal mass ejections (CME's). The input parameter distributions were formed from 100 sets of CME cone parameters derived from the Coned Model. The Coned Model employed image processing along with the bootstrap approach to automatically calculate cone parameter distributions from SOHO-LASCO imagery based on techniques described by Pulkkinen et al. [2010]. The input parameter distributions were used as input to WSA-ENLIL to calculate the temporal evolution of the …
Evaluation Of Interplanetary Magnetic Field Tracing Models Using Impulsive Seps, Brian P. Elliott
Evaluation Of Interplanetary Magnetic Field Tracing Models Using Impulsive Seps, Brian P. Elliott
Theses and Dissertations
Current Interplanetary Magnetic Field (IMF) models are evaluated in this study to determine which model(s) perform an accurate representation of this magnetic structure. These IMF models include the Parker Spiral model, the Potential Field Source Surface (PFSS) model, the Wang-Sheeley-Arge (WSA) model and the ENLIL model. Impulsive Solar Energetic Particles (SEPs) are used as tracers to determine the magnetic structure of the IMF and provide source locations for model comparisons. Each individual model is analyzed, compared to the identified solar source region and a longitude/latitude offset of these traces assigned. The model connection of the PFSS and Parker models is …