Whistler-mode chorus waves have recently drawn tremendous attention as an important mechanism for controlling the energetic electron flux in Earthâ€™s radiation belt. This dissertation aims to answer questions about whistler-mode chorus waves, such...
Radio relics are extended regions of synchrotron radio emission that have been found in the outskirts of a few dozen galaxy clusters. Relics are often associated with clusters undergoing merger activity. They are not associated optically with a...
The auroral zone is a rich source of natural radio emissions that can be observed in space and at ground-level. By studying these waves, scientists can gain insight into the plasma processes that generate them and use the near-Earth space...
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...
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...
Relativity (Physics). ; Anisotropy -- Mathematical models. ; Einstein field equations. ; Newtonian fluids. ; Astrophysics.
We study the effects of anisotropic pressure on the properties of spherically symmetric, gravitationally bound spheres. We consider the full general-relativistic and Newtonian treatment of this problem and obtain exact solutions for various forms...
Cosmic acceleration could be an effect of a ""dark energy"" fluid pervading the Universe. It could also be an indication that general relativity is not the correct theory of gravity at cosmological length scales. Unfortunately, observations of the...
After decades of searching we have yet to find the progenitor systems for type Ia supernovae. In fact most of what we know about this homogeneous class of supernovae is from spectral features associated with the incinerated remains of the C+O white...
A double-acceleration stage linear time of flight mass spectrometer (TOF MS) with Nd/YAG laser ablation cluster source was designed and constructed for cluster production, study and deposition. Cumulenic polycarbons SC n S ( n = 2-27) were...
Coherent states. Quantum field theory. Nonlinear theories.
In this thesis we study the properties of time-dependent, nontopological configurations and their effect on the macroscopic properties of a system described by a nonlinear field theory. These structures seem to be ubiquitous in relativistic field...
Since its discovery in the 1930's, the Cherenkov effect has been paramount in the development of high-energy physics research. It results in light emission from charged particles traveling faster than the local speed of light in a dielectric...
While Cherenkov emission was discovered more than eighty years ago, the potential applications of imaging this during radiation therapy have just recently been explored. With approximately half of all cancer patients being treated by radiation at...
The fluxes of radiation belt electrons are highly variable, due to a competition between various acceleration, loss, and transport processes. Studies of any of the processes are equally important. My study focuses on electron-EMIC (electromagnetic...
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...
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,...
Magnetic fields at all scales are prevalent in our universe. However, current cosmological models predict that initially the universe was bereft of large-scale fields. Standard magnetohydrodynamics (MHD) does not permit magnetogenesis; in the MHD...
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...
The main driving force behind the development of computers was the attempt to solve problems that would otherwise require a large amount of time to be solved. Despite the technological development that has made computers ubiquitous in daily lives,...
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...
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...
In this thesis data from four sounding rocket experiments (PHAZE II, SIERRA, RACE and HIBAR) are used to explore the high and medium frequency waves seen in the auroral ionosphere. All rockets were launched into active aurora and carried both...