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Hydrogen ion concentration, electron density, and proton gyrofrequency near satellites from asymptotic frequency-time profile of proton whistler near proton gyrofrequency
Electron density distribution in the f-2 layer of the ionosphere in winter, and the relation of the enhanced ionization to the so-called winters anomaly
Mathematical procedures and digital computer programs for converting observed topside curves into electron density profiles
On April 27, 1961 at 1502 EST a four-stage research rocket was fired from Wallops Island, Virginia, to measure the ionospheric electron density distribution by means of Seddon's CW propagation technique. This experimental technique is based upon the dispersive Doppler effect measured at two harmonically related frequencies, in this case f = 12.267 Mc and 6f = 73.6 Mc. The electron density profile measured above the peak of the F2 region is representative of a diffusive-equilibrium distribution in an isothermal ionosphere having a temperature of 1640 deg +/- 90 deg K. This result, when compared with satellite and other data, indicates that the upper ionosphere is in thermodynamic equilibrium.
A Super Arcas rocket, MISTI B, containing DC and RF probes, was launched as a part of the PMSE (Polar Mesosphere Summer Echoes) Salvo during the NLC-91 (Noctilucent Cloud) campaign to measure electron density irregularities with high spatial resolution. Measurements of large and small scale structures in the electron density were made on rocket ascent and descent at the altitudes of 86.5 and 88.5 +/- 0.5 km corresponding to the two altitudes of strongest backscatter recorded by the nearby CUPRI (Cornell University Portable Radar Interferometer) radar. Power spectra of the fluctuations shows two different structuring and scattering mechanisms exist at altitudes only 1 km apart. Since the rocket apogee was 89 km, the rocket was in the height range 88.5 +/- 0.5 km for 30 seconds giving an unusual measurement of horizontal structure over a distance of 5.5 km. Using the simultaneous DC and RF probe measurements of electron depletions and sharp gradient in the lower layer, the role of aerosols in creating these depletions and gradients is speculated upon.
F-region nightglow emissions of atomic oxygen - analysis of 6300 angstrom and electron density data
Diurnal variation in electron densities and temperatures in F region above Puerto-Rico, using backscatter measurements
We present observations of the forbidden coronal lines Fe XII 1242 A and 1349 A from active regions and from two flares, obtained by the SO82B slit spectrograph onboard Skylab. The line intensity ratio R = I(1242 A)/I(1349 A) is sensitive to electron density. We have calculated this ratio using recent atomic data, and obtained coronal electron densities at T = 1.5 x 10(exp 6) K for our observations. We find a range in N(sub e) of (0.5 to 7.2) x 10(exp 9)/cm(exp -3) for active regions, which is in good agreement with previous results from other diagnostic ratios in this temperature range, and of approximately (0.9 to 12) x 10(exp 9)/cm(exp -3) (or higher) for flares, which is generally low compared to previous flare results. The flare values employ particularly weak 1349 A observations and may not be reliable. From an observation of an active region just inside the solar limb, giving the best coverage in our data of both line profiles, we find a line width (FWHM) for both lines of 0.20 A, which corresponds to a nonthermal velocity of 18 km/sec.
Electron density profiles of E region in vicinity of geomagnetic equator measured by Nike-Apache rockets
Analytical methods of predicting electron density in rocket exhaust plumes based on detailed descriptions of flow regimes and chemical models
Measurement of average electron density in D region
Precursor electron densities measured in nitrogen and air ahead of shock waves, noting shock tube wall reflectivity
Ionosphere Topside Sounder program - electron density and geomagnetic field at Alouette I orbit
The current model for the polarized brightness (pB) spectrum has a decades-long history of progressively incorporating its dependence on electron density N(e), temperature T(e), and flow velocity in the radial direction V(e). The pBNe spectrum follows the exact shape of the photosphere spectrum, which is not smooth, which is expected from the thermal Doppler broadening of the photosphere spectrum due to the high coronal T(e). The pBN(e) spectrum is smooth, but the free coronal electrons remain static and unaffected by solar wind, and the pBN(e)T(e)V(e) spectrum is red-shifted by electrons seeing a red-shifted photosphere spectrum as they flow away from the Sun as solar wind, which takes a radial direction above 2.5 R from Sun center. In this article, we review the progress of the above three model pB spectra in describing the observations and highlight the differences, first by comparing the three model pB spectra against wavelength using a model for Ne and constant values for T(e) and V (e), and second by generating three model 2D pB maps by integrating over a selected wavelength region in the three model pB spectra along lines of sight passing through the 14 July 2000 (“Bastille Day”) coronal mass ejection (CME) model, which contains 3D information on N(e), T(e), and V e. In this regard, the COronal Diagnostic EXperiment (CODEX) on the International Space Station (ISS) in 2024 will measure N(e), T(e), and V(e) by matching the measured pB with modeled pBN(e)T(e)V(e) in selected wavelength regions using multiple filters.
The current model for the polarized brightness (pB) spectrum has a decades-long history of progressively incorporating its dependence on electron density Ne, temperature Te, and flow velocity in the radial direction V e . The pB N e spectrum follows the exact shape of the photosphere spectrum, which is not smooth, which is expected from the thermal Doppler broadening of the photosphere spectrum due to the high coronal T e ; the pB N e T e spectrum is smooth, but the free coronal electrons remain static and unaffected by solar wind, and the pB N e T e V e spectrum is red-shifted by electrons seeing a red-shifted photosphere spectrum as they flow away from the Sun as solar wind, which takes a radial direction above 2.5 R ⨀ from Sun center. In this article, we review the progress of the above three model pB spectra in describing the observations and highlight the differences, first by comparing the three model pB spectra against wavelength using a model for Ne and constant values for T e and V e , and second by generating three model 2D pB maps by integrating over a selected wavelengthregion in the three model pB spectra along lines of sight passing through the 14 July 2000 (“Bastille Day”) coronal mass ejection (CME) model, which contains 3D information on N e , T e , and V e . In this regard, the COronal Diagnostic EXperiment (CODEX) on the International Space Station (ISS) in 2024 will measure N e , T e , and V e by matching the measured pB with modeled pB N e T e V e in selected wavelength regions using multiple filters.
Diurnal variation in electron densities and temperatures in F region from backscatter measurements over Puerto Rico
Middle latitude changes in topside electron density during magnetic storm
Application of a viscous shock-layer analysis to the calculation of nonequilibrium-flow species distributions in the plasma layer of a blunt-nosed vehicle at high altitudes. The theoretical electron-density results obtained are in good agreement with those measured in flight for a hemisphere-9 deg cone entry vehicle. The flight measurements were obtained using electrostatic probes that protruded well into the shock layer. In addition, the theoretically obtained heavy-particle translational temperatures appear to agree fairly well with the electron temperatures that were measured in the flight experiments using voltage-swept thin-wire electrostatic probes. The influence of the reaction rate coefficients on the calculated electron densities has been assessed and shown to be within the uncertainty in the flight data. The theoretical results demonstrate the importance of including in the chemical model the positive ions N2(+), O2(+), N(+), and O(+), in addition to NO(+), for the high altitudes and velocities considered.