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...
Motivated by quantum mechanics and geometric optics, it is a long-standing problem whether the length spectrum of a compact Riemannian manifold can be recovered from its Laplace spectrum. One route to proving that the length spectrum depends on the...
The main research objective of this thesis is to address distributed target tracking for mobile sensor networks. Based on real-life limitations, we are particularly interested in mobile sensors with Limited Sensing Range (LSR). There are three...
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...
We present results from a modeling effort of simple shock phenomena in the Cygnus Loop and Cassiopeia A. Using multi-epoch MDM observations of a small, isolated cloud in the southwest region of the Cygnus Loop, we measure the velocity of the...
Riemannian manifolds. Singularities (Mathematics). Laplacian operator. Spectral theory (Mathematics). Riemann surfaces. Curves on surfaces. Geometry
Historically, inverse spectral theory has been concerned with the relationship between the geometry and the spectrum of compact Riemannian manifolds, where spectrum means the eigenvalue spectrum of the Laplace operator as it acts on smooth...
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...
A sample of 46 previously unidentified, intermediate- to high-redshift, near-infrared (NIR)-selected galaxy clusters have been discovered in the Andromeda catalog of the Oxford Dartmouth Thirty Degree Survey (ODTS). These clusters vary from low- to...