This thesis presents data from ground camera observations of the aurora conducted from Alaska during the winters of 2005 through 2007. In conjunction with these camera observations, conjugate radar observations of the auroral ionosphere were...
Medical imaging methods have become increasingly important in diagnosing diseases and assisting therapeutic treatment. In particular, early detection of breast cancer is considered as a critical factor in reducing the mortality rate of women....
The discovery of the Van Allen radiation belts in the 1958 was the first major discovery of the Space Age. There are two belts of energetic particles. The inner belt is very stable, but the outer belt is extremely variable, especially during...
The accelerated expansion of space in the Universe has been known for two decades. However, finding a plausible theory that describes this expansion is more difficult: Taking general relativity for granted requires us to stipulate the existence of...
We provide a theoretical model for a design involving a dc voltage biased Josephson junction (JJ) that strongly drives a high quality factor microwave cavity via the ac Josephson effect. We explore the rich classical dynamics of the resultant...
Since their discovery in laboratory plasmas in the 1920s, Langmuir waves have been observed to be ubiquitous in plasma environments, particularly in space plasmas. From the greater solar wind to planetary foreshocks and the auroral ionosphere,...
'The control of waves using periodic structures is crucial for modern optical, electromagnetic and acoustic devices such as diffraction gratings, filters, photonic crystals, solar cells, sensors, and absorbers. We present a high-order accurate...
Si-based quantum devices, including Si/SiGe quantum dots (QD), are promising candidates for spin-based quantum bits (quits), which are a potential platform for quantum information processing [1]. Meanwhile, qubit readout remains a challenging task...
The ionosphere is the primary source for heavy ions which are ubiquitous in the terrestrial magnetosphere. Low-altitude energization in the auroral ionosphere results in bulk heating and transverse acceleration of ions, which begin to upwell and/or...
Van Allen radiation belts -- Mathematical models. ; Magnetosphere -- Mathematical models. ; Magnetohydrodynamics -- Mathematical models.
The physics of geomagnetically-trapped radiation has been a topic of interest since the discovery of the Van Allen belts in 1958. As the energetic particles comprising these belts can pose a hazard to human activity in space, considerable effort...
Plasma instabilities. ; Ionospheric electron density. ; Ionosphere.
As a result of an unstable plasma stratification the nighttime equatorial ionosphere is subject to a variety of plasma instabilities known commonly as equatorial spread-F. In its fully developed form spread-F consists of large wedges of depleted...
Van Allen radiation belts -- Mathematical models. Electrons -- Diffusion -- Mathematical models. Magnetohydrodynamic waves -- Mathematical models.
It is becoming increasingly important to understand the dynamics of radiation belt energetic particles given their potentially hazardous effects on satellites and our ever-increasing dependence on those satellites. There is a need to determine...
Free electron lasers -- Experiments. ; Resonators -- Experiments.
A Smith-Purcell Free Electron Laser test-facility has been developed. The structure is used to conduct detailed explorations that novel resonator designs will have on tunability, start current and other performance criteria. Emphasis is on sources...
The Cerenkov Maser radiation is examined using linear and nonlinear theory. Linear theories for the gain in the single particle and the collective limits have been given previously. In this work, we show the connections between these two operating...
Measurement of the ionospheric thermal particle population bridges the two different communities of ground-based radar and space-based rocket studies, which have the common goal of characterizing heavy ion transport in the cusp/cleft region. We...
Eddy currents (Electric) -- Mathematical models. Electric generators -- Windings. Finite element method.
Magnetic components, such as transformers and inductors, are essential parts of most power electronics circuits. They usually are the largest components in the circuit, and also account for a large portion of the power loss. Reducing the volume of...
In this thesis we review the methods for computation of cosmological correlations in the early universe known as the in-in formalism which are then applied to the problem of magnetogenesis from inflation. For this computation, a power-law single...
The thesis is devoted to the effects of electromagnetic coupling between the Earth's magnetosphere and the active auroral ionosphere. The research has been focused, in particular, on the concept of ionospheric feedback instability. The feedback...
Auroras -- Alaska -- Observations. Magnetospheric currents. Electric currents. Magnetic fields.
Auroral downward-current regions balance the upward currents of visible auroral arcs. FAST satellite data show conclusive evidence to confirm that these downward current regions (DCR) contain positive potential structures with diverging DC electric...