Physics Commons^™

Explicit Construction Of First Integrals For The Toda Flow On A Classical Simple Lie Algebra, Patrick Seegmiller

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Toda flow is a generalization of a dynamical system describing the interaction of particles in a one-dimensional crystal. The concepts and energy and conservation are prominent in the study of dynamical systems, and quantities which remain the same over the evolution of a system provide valuable insights into the system’s behavior. In the realm of mathematics these quantities are called first integrals, or integrals of motion. This paper provides a background for study of the Toda flow, a verification of its integrability, and programming code for finding these quantities which remain unchanged over the evolution of the system.

Optical Characterization Of Carbon Nanotube Forests, Brian D. Wood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Carbon nanotube forests are vertically grown tubular formations of graphene. Due to their inherent microstructure and geometry, they are ideal light absorbers over a broad spectrum, making this material an excellent absorber in applications such as radiometry, optical calibration, and stray light suppression. Samples were made with several growth conditions and substrates to provide forests of different morphologies. Optical data of these samples were gathered by taking spectroscopic reflectance and transmittance measurements in the mid-infrared spectral range. Results were correlated to the various forest morphologies. From this, the conditions necessary to maximize the absorption of the forests were found and …

The Role Of Thermospheric Neutral Winds In The Mid-Latitude Ionospheric Evening Anomalies, Levan Lomidze

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Earth's ionosphere, which is the ionized part of the upper atmosphere, plays a very important role in ground- and satellite-based radio communication and navigation. During the last half century, a considerable experimental, theoretical, and modeling effort has been directed towards understanding the physical processes that affect the variation of the ionization in the ionosphere at various spatial and temporal scales. Even though tremendous progress has been made in many directions of ionospheric research, many questions remain to be answered.

One of the intriguing features in the ionosphere is an anomalous evening enhancement that occurs over certain mid-latitude locations, where …

Altitudinal Variability Of Quiet-Time Plasma Drifts In The Equatorial Ionosphere, Debrup Hui

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the modern world, we increasingly depend on space-based systems for our communication, positioning, and navigation systems. These systems depend on electromagnetic waves propagating through the ionosphere. The ionosphere is the medium in the upper atmosphere where, due to presence of the charged atomic and molecular particles and electrons collectively known as plasma, it influences the traveling electromagnetic waves following laws of electrodynamics. Improved models for predicting space weather conditions require improved knowledge of the drifts of these plasmas in the ionosphere. This study is focused on climatology of the altitudinal variations of these plasma drifts in the equatorial latitudes. …

A Study Of The Dayside High-Latitude Ionospheric Electrodynamics During Extended Solar Minimum, Janelle V. Jenniges

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research investigated how electric fields, currents, and charged particles in Earth's high-latitude ionosphere respond to changing input from the sun. The ionosphere surrounds the entire Earth, makes radio communication possible, and can significantly degrade satellite communications and geo-positioning (navigation) capabilities. Many satellites fly within the ionosphere where a solar storm can cause increased satellite drag or destroy onboard electronics. Therefore, understanding and correctly predicting the behavior of this environment is important, and the results from this research will be used to improve current ionospheric models.

A relationship between the level of magnetic activity on Earth due to changes in …