A5082954466- Ionosphere and magnetosphere dynamics
- Solar and Space Plasma Dynamics
- GNSS positioning and interference
- Earthquake Detection and Analysis
- Atmospheric Ozone and Climate
- Geomagnetism and Paleomagnetism Studies
- Geophysics and Gravity Measurements
- Geophysical and Geoelectrical Methods
- Plant responses to water stress
- Rice Cultivation and Yield Improvement
- Plasma Diagnostics and Applications
- Magnetic confinement fusion research
- Laser-induced spectroscopy and plasma
- Cardiovascular and Diving-Related Complications
- Oceanographic and Atmospheric Processes
- Geology and Paleoclimatology Research
- Plasma Applications and Diagnostics
- Atomic and Subatomic Physics Research
- Simulation Techniques and Applications
- Plant Genetic and Mutation Studies
Spire Corporation (United States)
2019
United States Naval Research Laboratory
2012-2015
Sotera Defense Solutions (United States)
2013-2014
National Academies of Sciences, Engineering, and Medicine
2012
Boston College
2009
The University of Texas at Dallas
2005
The Naval Research Laboratory three‐dimensional simulation code SAMI3/ESF is used to study the response of postsunset ionosphere circular gravity waves. We model coupling both (local) and plane wave (nonlocal) waves bottomside F layer as a mechanism for triggering equatorial plasma bubbles. Results support hypothesis that nonplane can more strongly couple than also show seed depends on growth rate local electron density at position wave.
Abstract. Measurements of total electron content (TEC) using 263 GPS receivers located in the North and South America continents are presented to demonstrate simultaneous existence traveling ionospheric disturbances (TID) at high, mid, low latitudes, both Northern Southern Hemispheres. The TID observations pertain magnetically disturbed period 29–30 October 2003 also known as Halloween storm. excellent quality TEC measurements makes it possible calculate remove diurnal variability then...
We examine the large‐scale properties of three classes equatorial topside plasma depletions referred to as channels. In order increasing zonal width and internal substructuring, we study simple channels, multichannels, superchannels. find that peaks in channel activity are centered on 0° (African sector) 180° (Western Pacific sector). Superchannels found strongly dominate African sector, whereas multichannels sector. Within relative proportions remain stable all seasons. dominant seasons...
This scientific report presents the results of a dedicated experiment that was conducted within framework Low-latitude ionospheric Sensor Network (LISN) observatory to measure characteristics medium-scale (hundreds km) Traveling Ionospheric Disturbances (TIDs) as they transit through low-latitude ionosphere. A small array 3 GPS receivers separated by 4-5 km placed in triangular configuration installed near Huancayo Peru possessing several radio-interferometer. During campaign days, 17–30...
Abstract We present and discuss two algorithms of the class known as Image Space Reconstruction Algorithms (ISRAs) that we are applying to solution large‐scale ionospheric tomography problems. ISRAs have several desirable features make them useful for tomography. In addition producing nonnegative solutions, amenable sparse‐matrix formulations fast, stable, robust. results our studies types ISRA: Least Squares Positive Definite Richardson‐Lucy algorithms. compare their performance...
Abstract For the first time, equatorial plasma depletions (EPDs) have been imaged in longitude‐altitude plane using radiotomography. High‐resolution (~10 km) reconstructions of electron density were derived from total content (TEC) measurements provided by a receiver array Peru. TEC data obtained VHF/UHF signals transmitted Coherent Electromagnetic Radio Tomography (CERTO) beacon on C/NOFS satellite. EPDs generated premidnight observed near dawn. On one night, bubble densities highly...
Abstract The Special Sensor Ultraviolet Limb Imager (SSULI) instruments are ultraviolet limb scanning sensors that fly on the Defense Meteorological Satellite Program F16‐F19 satellites. SSULIs cover 80–170 nm wavelength range which contains emissions at 91 and 136 nm, produced by radiative recombination of ionosphere. We invert 91.1 emission tomographically using a newly developed algorithm includes optical depth effects due to pure absorption resonant scattering. present details our...
The CERTO radio beacon on the C/NOFS satellite sends VHF/UHF signals at 150 and 400 MHz to provide measurements of integrated electron density or Total Electron Content (TEC) by an east-west chain ground receivers in Peru. Computerized Ionospheric Tomography (CIT) is used convert TEC data into two-dimensional images densities with maximum 5 × 5 km resolution Longitude-Altitude space. These are updated every 95 min as passes over receiver network its low-latitude orbit inclination 12°. 2-D,...
Abstract The 135.6‐nm emission of atomic oxygen has become a workhorse for satellite remote sensing the nighttime ionosphere. Previous work on interpreting established importance properly modeling mutual neutralization and radiative recombination contributions to volume rate emphasized transfer transport radiation. Recently, we developed published new inversion approach called Volume Emission Rate Tomography, which handles radiation as part tomography process. We compare electron density...
Abstract We present the Volume Emission Rate Tomography (VERT) technique for inverting satellite‐based, multisensor limb and nadir measurements of atmospheric ultraviolet emission to create whole‐orbit reconstructions volume rate. The VERT approach is more general than previous ionospheric tomography methods because it can reconstruct rate field irrespective particular excitation mechanisms (e.g., radiative recombination, photoelectron impact excitation, energetic particle precipitation in...
For the first time, post-midnight Equatorial Plasma Depletions (EPDs) have been imaged in longitude-altitude plane using radio-beacon tomography. High-resolution (~10 km × 10 km) electron-density reconstructions were created area between approximately -90° and -55° longitude near geomagnetic equator. The Total Electron Content (TEC) measurements from an NRL receiver array sited Peru MART inversion algorithm. TEC was derived 150 400 MHz signals transmitted by CERTO beacon on C/NOFS satellite....