Mathematical model of radio sounding of the ionosphere from satellite at heights below the electron density maximum

2006 ◽  
Vol 46 (2) ◽  
pp. 222-229 ◽  
Author(s):  
N. G. Kotonaeva
Keyword(s):  
Mathematical Model ◽  
Electron Density ◽  
Density Maximum ◽  
Radio Sounding

scholarly journals An investigation of the ionospheric F region near the EIA crest in India using OI 777.4 and 630.0 nm nightglow observations

2018 ◽  
Vol 36 (3) ◽  
pp. 809-823 ◽  
Author(s):  
Navin Parihar ◽  
Sandro Maria Radicella ◽  
Bruno Nava ◽  
Yenca Olivia Migoya-Orue ◽  
Prabhakar Tiwari ◽  
...  
Keyword(s):  
Electron Density ◽  
Gravity Waves ◽  
Satellite Mission ◽  
Low Latitude ◽  
Density Maximum ◽  
Density Profiles ◽  
F Region ◽  
Equatorial Ionization Anomaly ◽  
Low Latitude Ionosphere ◽  
Electron Density Profiles

Abstract. Simultaneous observations of OI 777.4 and OI 630.0 nm nightglow emissions were carried at a low-latitude station, Allahabad (25.5° N, 81.9° E; geomag. lat.  ∼  16.30° N), located near the crest of the Appleton anomaly in India during September–December 2009. This report attempts to study the F region of ionosphere using airglow-derived parameters. Using an empirical approach put forward by Makela et al. (2001), firstly, we propose a novel technique to calibrate OI 777.4 and 630.0 nm emission intensities using Constellation Observing System for Meteorology, Ionosphere, and Climate/Formosa Satellite Mission 3 (COSMIC/FORMOSAT-3) electron density profiles. Next, the electron density maximum (Nm) and its height (hmF2) of the F layer have been derived from the information of two calibrated intensities. Nocturnal variation of Nm showed the signatures of the retreat of the equatorial ionization anomaly (EIA) and the midnight temperature maximum (MTM) phenomenon that are usually observed in the equatorial and low-latitude ionosphere. Signatures of gravity waves with time periods in the range of 0.7–3.0 h were also seen in Nm and hmF2 variations. Sample Nm and hmF2 maps have also been generated to show the usefulness of this technique in studying ionospheric processes.

The effect of disturbed-time electric fields on the inner plasmasphere

1994 ◽  
Vol 12 (4) ◽  
pp. 296-303 ◽  
Author(s):  
H. F. Balmforth ◽  
R. J. Moffett ◽  
A. J. Smith ◽  
G. J. Bailey
Keyword(s):  
Mathematical Model ◽  
Electric Field ◽  
Electron Density ◽  
Electric Fields ◽  
Doppler Shift ◽  
Group Delay ◽  
Whistler Mode ◽  
L Value

Abstract. Results from a mathematical model provide a description of the mid-latitude, low L-shell ionosphere and plasmasphere. Variations in the composition and dynamics of the plasmasphere and changes in the nature of the coupling between the plasmasphere and the ionosphere are studied for moderately disturbed conditions. Modelled results are compared to group delay and Doppler shift measurements of whistler mode signals at Faraday, Antarctica (L ≈ 2.5), to investigate the effects of disturbed time electric fields on the inner plasmasphere and ionosphere. The disturbed time electric field causes a rapid outward drifting of the plasma leading to a decrease in modelled plasmaspheric electron density at a fixed L-value, which agrees with experimental observations. During the periods of outward drift, the modelled coupling flux is upwards to the plasmasphere which can lead to a significant depletion of NmF2 values.

Vibrational nitrogen concentration in the ionosphere and its dependence on season and solar cycle

1995 ◽  
Vol 13 (11) ◽  
pp. 1164-1171 ◽  
Author(s):  
A. E. Ennis ◽  
G. J. Bailey ◽  
R. J. Moffett
Keyword(s):  
Mathematical Model ◽  
Solar Cycle ◽  
Electron Density ◽  
Geomagnetic Field ◽  
Nitrogen Concentration ◽  
Time Dependent ◽  
Electron Content ◽  
Vibrationally Excited ◽  
F Region ◽  
Excited Nitrogen

Abstract. A fully time-dependent mathematical model, SUPIM, of the Earth's plasmasphere is used in this investigation. The model solves coupled time-dependent equations of continuity, momentum and energy balance for the O+, H+, He+, N+2, O+2, NO+ ions and electrons; in the present study, the geomagnetic field is represented by an axial-centred dipole. Calculation of vibrationally excited nitrogen molecules, which has been incorporated into the model, is presented here. The enhanced model is then used to investigate the behaviour of vibrationally excited nitrogen molecules with F10.7 and solar EUV flux, during summer, winter and equinox conditions. The presence of vibrational nitrogen causes a reduction in the electron content. The diurnal peak in electron content increases linearly up to a certain value of F10.7, and above this value increases at a lesser rate, in agreement with previous observations and modelling work. The value of F10.7 at which this change in gradient occurs is reduced by the presence of vibrational nitrogen. Vibrational nitrogen is most effective at F-region altitudes during summer daytime conditions when a reduction in the electron density is seen. A lesser effect is seen at equinox, and in winter the effect is negligible. The summer reduction in electron density due to vibrational nitrogen therefore reinforces the seasonal anomaly.

scholarly journals Plasma Spectroscopy Diagnostics of V2O5 at a Variable of Operating Power and Pressure With Radio Frequency Magnetron Sputtering.

2019 ◽  
Vol 16 (1) ◽  
pp. 0209
Author(s):  
Salman Et al.
Keyword(s):  
Magnetron Sputtering ◽  
Radio Frequency ◽  
Electron Temperature ◽  
Electron Density ◽  
Gas Pressure ◽  
Rf Power ◽  
Plasma Parameters ◽  
Density Maximum ◽  
Density Decrease ◽  
Sputtering Power

   In this paper, we investigate the basic characteristics of "magnetron sputtering plasma" using the target V2O5. The "magnetron sputtering plasma" is produced using "radio frequency (RF)" power supply and Argon gas. The intensity of the light emission from atoms and radicals in the plasma measured by using "optical emission spectrophotometer", and the appeared peaks in all patterns match the standard lines from NIST database and employed are to estimate the plasma parameters, of computes electron temperature and the electrons density. The characteristics of V2O5 sputtering plasma at multiple discharge provisos are studied at the "radio frequency" (RF) power ranging from 75 - 150 Watt and gas pressure (0.03, 0.05 and  0.007) torr.  One can observe that the intensity of the emission lines increases with increasing the sputtering power. We find that the electron temperature excess drastically from 0.95 eV to 1.11eV when the emptying gas pressure excess from 0.03 to 0.05 Torr. On other hand excess electron temperature from 0.9 to 1.01 eV with increasing sputtering power from 100 to 125 Watt, while the electron density decrease from 5.9×1014 to 4.5×1014 cm-3 with increasing sputtering power. and electron density decrease with increasing of pressure from 4.25×1014 to 2.80×1014 cm-3, But the electron density maximum values  5.9×1014 at pressure  0.03 Torr.

scholarly journals The Behaviour of a Chapman Layer in the Night F2 Region of the Ionosphere, Under the Influence of Gravity, Diffusion, and Attachment

1956 ◽  
Vol 9 (4) ◽  
pp. 436 ◽  
Author(s):  
RA Duncan
Keyword(s):  
Electron Density ◽  
Density Maximum ◽  
Attachment Coefficient ◽  
Equilibrium Height

It is shown that, in the presence of diffusion, gravity, and attachment, a Chapman layer, no matter what its height, maintains its shape, decaying uniformly with an effective attachment coefficient equal to the true attachment coefficient at the height of the electron density maximum; and that, at the same time, the layer drifts bodily towards an equilibrium height.

scholarly journals An investigation of the ionospheric F-region near the EIA crest in India using OI 777.4 and 630.0 nm nightglow observations

2018 ◽  
Author(s):  
Navin Parihar ◽  
Sandro M. Radicella ◽  
Bruno Nava ◽  
Yenca Olivia Migoya Orue ◽  
Prabhakar Tiwari ◽  
...  
Keyword(s):  
Electron Density ◽  
Gravity Waves ◽  
Satellite Mission ◽  
Low Latitude ◽  
Density Maximum ◽  
Density Profiles ◽  
F Region ◽  
Equatorial Ionization Anomaly ◽  
Low Latitude Ionosphere ◽  
Electron Density Profiles

Abstract. Simultaneous observations of OI 777.4 nm and OI 630.0 nm nightglow emissions were carried at a low latitude station, Allahabad (25.5º N, 81.9º E, geomag. lat. ~16.30º N), located near the crest of Appleton anomaly in India during September–December 2009. This study attempts to examine the behaviour of the F region of ionosphere using airglow derived parameters. Using an empirical approach put forward by Makela et al. (2001), firstly, we propose a novel technique to calibrate OI 777.4 and 630.0 nm emission intensities using Constellation Observing System for Meteorology, Ionosphere, and Climate/Formosa Satellite Mission 3 (COSMIC/FORMOSAT-3) electron density profiles. Next, electron density maximum (Nm) and its height (hmF2) of the F-layer have been derived from the information of two calibrated intensities. Nightglow derived Nm and hmF2 were in reasonable agreement with few measurements reported earlier. Nm and hmF2 were used to study the behaviour of the F-region over Allahabad on the limited number of nights. Nocturnal variation of Nm showed the signatures of the retreat of equatorial ionization anomaly (EIA) and mid-night temperature maximum (MTM) phenomenon that are usually observed in the equatorial and low-latitude ionosphere. Signatures of gravity waves having period in the range of 0.7–3.0 h were also seen in Nm and hmF2 variations. Sample Nm and hmF2 maps have also been generated to show the usefulness of this technique in studying the ionospheric processes.

scholarly journals Plasma Spectroscopy Diagnostics of V2O5 at a Variable of Operating Power and Pressure With Radio Frequency Magnetron Sputtering.

2019 ◽  
Vol 16 (1(Suppl.)) ◽  
pp. 0209
Author(s):  
Salman Et al.
Keyword(s):  
Magnetron Sputtering ◽  
Radio Frequency ◽  
Electron Temperature ◽  
Electron Density ◽  
Gas Pressure ◽  
Rf Power ◽  
Plasma Parameters ◽  
Density Maximum ◽  
Density Decrease ◽  
Sputtering Power

   In this paper, we investigate the basic characteristics of "magnetron sputtering plasma" using the target V2O5. The "magnetron sputtering plasma" is produced using "radio frequency (RF)" power supply and Argon gas. The intensity of the light emission from atoms and radicals in the plasma measured by using "optical emission spectrophotometer", and the appeared peaks in all patterns match the standard lines from NIST database and employed are to estimate the plasma parameters, of computes electron temperature and the electrons density. The characteristics of V2O5 sputtering plasma at multiple discharge provisos are studied at the "radio frequency" (RF) power ranging from 75 - 150 Watt and gas pressure (0.03, 0.05 and  0.007) torr.  One can observe that the intensity of the emission lines increases with increasing the sputtering power. We find that the electron temperature excess drastically from 0.95 eV to 1.11eV when the emptying gas pressure excess from 0.03 to 0.05 Torr. On other hand excess electron temperature from 0.9 to 1.01 eV with increasing sputtering power from 100 to 125 Watt, while the electron density decrease from 5.9×1014 to 4.5×1014 cm-3 with increasing sputtering power. and electron density decrease with increasing of pressure from 4.25×1014 to 2.80×1014 cm-3, But the electron density maximum values  5.9×1014 at pressure  0.03 Torr.

Sign in / Sign up

Export Citation Format

Share Document