Numerical modeling of the global heliosphere provides key insights into the physics of the outer heliosphere. The solar wind data utilized by these models impacts their accuracy and should be as close as possible to the actual solar wind. Ideally,...
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...
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...
Loss processes greatly impact the dynamics of the Earth's radiation belts. In 1996, a balloon-borne germanium detector flown over Kiruna, Sweden detected the first terrestrial X-rays with energies on the order of 1 MeV. The spectrum for these...
Currently, the hypothesis that discrete auroral arcs are produced by fluxes of magnetospheric electrons accelerated along the ambient magnetic field into the ionosphere by linear/non-linear mechanisms associated with magnetic field-aligned currents...
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...
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...
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...
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...
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...
The Dartmouth Stellar Evolution Program, a state of the art stellar evolution code, has been modified and expanded to increase its versatility. The modifications include: the ability to self-consistently model stars with arbitrary chemical...
Space plasmas. ; Magnetopause. ; Solar wind. ; Magnetic flux. ; Plasma astrophysics.
Two types of two-dimensional (2-D), coherent (time-stationary) space plasma structures, described by one-fluid, magnetostatic and isotropic plasma theory, are examined. One is the internal structure of the Earth's magnetopause and the other is...
Electric fields in the high-latitude regions of Earth's ionosphere are an important component of the coupled magnetosphere-ionosphere-thermosphere system. Characterizing the average behavior of these fields (or the corresponding drifts) is useful...
I present new wide-field photometry of several globular clusters including: BVI ground-based photometry and VI space-based photometry for the globular cluster M92 (NGC 6341) BVI photometry for M2 (NGC 7089), M3 (NGC 5272), and M14 (NGC 6402) and...
Magnetosphere -- Mathematical models. Magnetic reconnection -- Mathematical models.
In this thesis we present the results of two studies of magnetic reconnection at the dayside magnetopause using the Lyon-Fedder-Mobarry magnetospheric simulation code. The first study examined the global properties of reconnection as a function of...
Earth's high latitude ionosphere, highly disturbed by particle and energy inputs and associated aurora, is the stage for plasma wave activity across a wide range of frequencies. These waves often exhibit strikingly distinct time-frequency structure...
The ability to forecast the weather of the geospace environment depends critically on the ability to accurately model the dynamics of the coupled magnetosphere-ionosphere (MI) system. The MI interaction involves a set of electrodynamic and plasma...
A polynomial is a product of distinct cyclotomic polynomials if and only if it is a divisor over [Special characters omitted.] [x ] of xn - 1 for some positive integer n. In this thesis, we will examine two natural questions concerning the divisors...
The ionosphere is an important source of plasma in the magnetosphere, especially during geomagnetic storms. While satellite data has confirmed this population of ions, their effect on the dynamics of the magnetosphere-ionosphere (MI) system is not...
There is a renewed interest in the study of the radiation belts with the recent launch of the Van Allen Probes satellites. The mechanisms that drive the global response of the radiation belts to geomagnetic storms are not yet well understood....