Documents in the NTIS Technical Reports collection are the results of federally funded research. They are directly submitted to or collected by NTIS from Federal agencies for permanent accessibility to industry, academia and the public.  Before purchasing from NTIS, you may want to check for free access from (1) the issuing organization's website; (2) the U.S. Government Printing Office's Federal Digital System website http://www.gpo.gov/fdsys; (3) the federal government Internet portal USA.gov; or (4) a web search conducted using a commercial search engine such as http://www.google.com.
Accession Number ADA564533
Title Numerical Simulation and Forecast of Equatorial Spread F Under Realistic Postsunset Conditions.
Publication Date Jan 2012
Media Count 16p
Personal Author D. L. Hysell H. A. Aveiro
Abstract A fully three-dimensional numerical simulation of plasma density irregularities in the postsunset equatorial F region ionosphere leading to equatorial spread F (ESF) has been developed. The simulation evolves under realistic background conditions including bottomside plasma shear flow and vertical current. It has been initialized and driven in accordance with background measurements obtained from the Air Force C/NOFS satellite, the Jicamarca Radio Observatory, the Altair radar on Kwajalein, and other instruments. Simulations are seeded with white noise alone and are, in that sense, agnostic with respect to the required, underlying seed mechanism. A combination of generalized Rayleigh Taylor (gRT) and collisional shear instability (CSI) has been found to produce growing waveforms with key features that agree with satellite and ground-based radar observations in several important respects, including their gross morphology, development rates, and magnetic signatures. The transient response of CSI is consistent with the observation of bottomside waves with wavelengths close to 30 km, whereas the steady-state behavior of the combined instability can account for the 100+ km wavelength waves that predominate in the F region.
Keywords Air force
Artificial satellites
Background
Behavior
Collisions
Consistency
Density
F region
Forecasting
Frequency
Ground based
Instability
Instrumentation
Magnetic signatures
Mathematical models
Measurement
Morphology
Numerical analysis
Observation
Plasmas(Physics)
Radar
Rates
Response
Seeding
Shear flow
Shear properties
Simulation
Spread f
Steady state
Three dimensional
Transients
Vertical orientation
Waveforms
Waves
White noise

 
Source Agency Non Paid ADAS
NTIS Subject Category 46G - Plasma Physics
Corporate Author Cornell Univ., Ithaca, NY. Dept. of Earth and Atmospheric Sciences.
Document Type Technical report
Title Note Final rept. Apr 2009-Jan 2012.
NTIS Issue Number 1303
Contract Number FA9550-09-1-0337

Science and Technology Highlights

See a sampling of the latest scientific, technical and engineering information from NTIS in the NTIS Technical Reports Newsletter

Acrobat Reader Mobile    Acrobat Reader