Two-dimensional numerical simulation of O-mode to Z-mode conversion in the ionosphere

Cannon, Patrick and Honary, Farideh and Borisov, N. (2016) Two-dimensional numerical simulation of O-mode to Z-mode conversion in the ionosphere. Journal of Geophysical Research: Space Physics, 121 (3). pp. 2755-2782. ISSN 2169-9402

[thumbnail of ModeConversionPaper_PCannon]
Preview
PDF (ModeConversionPaper_PCannon)
ModeConversionPaper_PCannon.pdf - Accepted Version

Download (8MB)
[thumbnail of Cannon_et_al-2016-Journal_of_Geophysical_Research-_Space_Physics]
Preview
PDF (Cannon_et_al-2016-Journal_of_Geophysical_Research-_Space_Physics)
Cannon_et_al_2016_Journal_of_Geophysical_Research_Space_Physics.pdf - Published Version
Available under License Creative Commons Attribution.

Download (5MB)

Abstract

Experiments in the illumination of the F region of the ionosphere via radio frequency waves polarized in the ordinary mode (O-mode) have revealed that the magnitude of artificial heating-induced effects depends strongly on the inclination angle of the pump beam, with a greater modification to the plasma observed when the heating beam is directed close to or along the magnetic zenith direction. Numerical simulations performed using a recently developed finite-difference time-domain (FDTD) code are used to investigate the contribution of the O-mode to Z-mode conversion process to this effect. The aspect angle dependence and angular size of the radio window for which conversion of an O-mode pump wave to the Z-mode occurs is simulated for a variety of plasma density profiles including 2-D linear gradients representative of large-scale plasma depletions, density-depleted plasma ducts, and periodic field-aligned irregularities. The angular shape of the conversion window is found to be strongly influenced by the background plasma profile. If the Z-mode wave is reflected, it can propagate back toward the O-mode reflection region leading to resonant enhancement of the electric field in this region. Simulation results presented in this paper demonstrate that this process can make a significant contribution to the magnitude of electron density depletion and temperature enhancement around the resonance height and contributes to a strong dependence of the magnitude of plasma perturbation with the direction of the pump wave.

Item Type:
Journal Article
Journal or Publication Title:
Journal of Geophysical Research: Space Physics
ID Code:
78894
Deposited By:
Deposited On:
05 May 2016 12:32
Refereed?:
Yes
Published?:
Published
Last Modified:
18 Dec 2023 01:36