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Geofísica internacional
On-line version ISSN 2954-436XPrint version ISSN 0016-7169
Geofís. Intl vol.44 n.4 Ciudad de México Oct./Dec. 2005
Articles
A model of enhanced electron concentration irregularities in the ionosphere: Perturbation amplitudes and hydrodynamic effects
1Universidad Nacional de Tucumán, Argentina
A bidimensional model is proposed to perform computer simulations of enhanced electron concentration irregularities, in an extended altitude range centered at the bottom of the F layer, and including the dependence of collision and recombination frequencies on density. The model is tested with different perturbation amplitudes in a limited fringe. We find that amplitudes in a medium range are more effective as a destabilising effect. All results confirm the hydrodynamic Rayleigh-Taylor prediction.
KEY WORDS: Ionosphere; electron concentration irregularities; Rayleigh-Taylor instability; hydrodynamic effect; perturbation amplitude
Se propone un modelo bidimensional para realizar simulaciones computacionales de irregularidades de concentración electrónica, en un rango extendido de altitud centrado en la base de la capa F, e incluyendo la dependencia de las frecuencias de colisiones y de recombinación, con la densidad. El modelo se prueba con diferentes amplitudes de perturbación en una franja limitada. Se encuentra que las amplitudes en un rango medio son más efectivas como efecto desestabilizante. Todos los resultados confirman la predicción de Rayleigh-Taylor hidrodinámica.
PALABRAS CLAVE: Ionósfera; irregularidades de concentración electrónica; inestabilidad de Rayleigh-Taylor; efecto hidrodinámico; amplitud de perturbación
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Received: September 20, 2004; Accepted: April 20, 2005
This is an open-access article distributed under the terms of the Creative Commons Attribution License
