D-Region Mobility Spectrometer
D-region mobility and constituents abundance spectrometer device based on continuum concepts
MASS SPECTROMETER↗
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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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A time-of-flight mass spectrometer suitable for ionospheric composition investigations
Time-of-flight spectrometer for examining ionospheric ion density in D and E regions
Diem, H. T.↗
A summary of blunt probe theory and experimental results.
Day and nighttime electron and ion density profiles in lower ionosphere deduced from blunt probe theory and measurements
Baker, D. C.↗
Calculations of diurnal changes in the exosphere.
Exosphere diurnal and latitudinal variations in electron and proton content, ion composition, and electron, proton and positive O ion densities
Titheridge, J. E.↗
Emissive probes for plasma potential measurements on the SERT II spacecraft.
Emissive probes for measuring plasma potentials over different ion density ranges on SERT spacecraft, detailing calibration and mechanical and electronic configurations
Daley, H. L.↗
MHD Rankine-Hugoniot equations applied to earth's bow shock.
MHD Rankine-Hugoniot equations for ion density, thermal pressure and convective velocity magnitude and orientation during Pioneer 6 traversal of earth bow shock
Mihalov, J. D.↗
Effects of secondary electron emission on electron trap measurements in the magnetosphere and solar wind
Spacecraft surface secondary electron emission effects on electron trap measurements in magnetosphere and solar wind, noting agreement with positive ion densities
Parker, L. W.↗
Emissive probes for plasma potential measurements on the SERT II spacecraft
Emissive probes for measuring plasma potentials over different ion density ranges on SERT spacecraft, detailing calibration and mechanical and electronic configurations
Daley, H. L.↗
Thermal diffusion in the F2-region of the ionosphere
Thermal diffusion effects on F 2 region ion densities, deriving diffusion coefficients for partially ionized atomic oxygen plasma
Schunk, R. W.↗
Minor ion diffusion in the F2-region of the ionosphere
Minor ion diffusion coefficients in F 2 region, noting Coulomb collisions role in ion density sensitivity to ionospheric fluxes
Schunk, R. W.↗
Ionospheric observations during the annular solar eclipse of 20 May 1966. V - Interpretation of observed results
Ionospheric Lyman alpha intensities and electron and positive ion densities during solar eclipse of 20 May 1966, discussing recombination model
Anastassiades, M.↗
Polarization of proton whistlers
Whistler-mode waves circular polarization measurement by OGO 6 satellite, noting application to hiss, chorus and ion density studies
Smith, R. L.↗
On the construction and use of a simple ionospheric model
Ionospheric computer model, describing electron and ion densities in middle latitudes as function of latitude, longitude, altitude, season, time and solar activity
Nisbet, J. S.↗
Plasma transport in the topside polar ionosphere
Polar ionospheric plasma transport, predicting ion density profiles from ionospheric processes models consistent with polar wind theory
Banks, P. M.↗
Measurements of plasma parameters in a simulated thermionic converter
Cesium-filled thermionic energy converters are examined as candidate electrical energy sources in spacecraft requiring tens to hundreds of kilowatts of electric power. The high operating temperatures necessary for a large specific power and high efficiency inevitably impose stringent constraints on the converter fabrication to achieve the desired reliability of the power system. The converter physics for reducing operating temperatures and cesium plasma losses are studied to achieve high reliability without sacrificing the power performance of the converters. Various cesium parameters which affect the converter performance are: (1) electron temperatures, (2) plasma ion densities, and (3) electric potential profiles. These were investigated using a Langmuir probe in a simulated converter. The parameters were measured in different cesium discharge modes.
Shimada, K.↗
Electrostatic-probe measurements of plasma parameters for two reentry flight experiments at 25000 feet per second
Unique plasma diagnostic measurements at high altitudes from two geometrically similar blunt body reentry spacecraft using electrostatic probe rakes are presented. The probes measured the positive ion density profiles (shape and magnitude) during the two flights. The probe measurements were made at eight discrete points (1 cm to 7 cm) from the vehicle surface in the aft flow field of the spacecraft over the altitude range of 85.3 to 53.3 km (280,000 to 175,000 ft) with measured densities of 10 to the 8th power to 10 to the 12th power electrons/cu cm, respectively. Maximum reentry velocity for each spacecraft was approximately 7620 meters/second (25,000 ft/sec). In the first flight experiment, water was periodically injected into a flow field which was contaminated by ablation products from the spacecraft nose region. The nonablative nose of the second spacecraft thereby minimized flow field contamination. Comparisons of the probe measured density profiles with theoretical calculations are presented with discussion as to the probable cause of significant disagreement. Also discussed are the correlation of probe measurements with vehicle angle of attack motions and the good high altitude agreement between electron densities inferred from the probe measurements, VHF antenna measurements, and microwave reflectometer diagnostic measurements.
Jones, W. L., Jr.↗
Model development of supersonic trough wind with shocks
The time dependent one dimensional hydrodynamic equations describe the evolution of the thermal plasma flow along closed magnetic field lines outside of the plasmasphere. The convection of the supersonic polar wind onto a closed fieldline results in the assumed formation of collisionless plasma shocks. These shocks move earthward as the field line with its frozen-in plasma remains fixed or contracts with time to smaller L coordinates. The high equatorial plasma temperature (of the order of electron volts) produced by the shock process decreases with time if the flow is isothermal but it will increase if the contraction is under adiabatic conditions. Assuming adiabaticity a peak in the temperature forms at the equator in conjunction with a depression in the ion density. After an initial contraction, if the flux tube drifts to higher L coordinates the direction of the shock motion can be reversed so that the supersonic region will expand along the field line towards the state characterizing the supersonic polar wind. A rapid expansion will lower the equatorial density while the temperature decreases with time under adiabatic but not isothermal conditions.
Grebowsky, J. M.↗
Probe measurements of a cesium plasma in a simulated thermionic energy converter
Cesium-filled thermionic energy converters are considered as electrical energy sources in future spacecraft requiring tens to hundreds of kilowatts of electric power. The high operating temperatures necessary for a large specific power and high efficiency impose stringent constraints on the converter fabrication. The converter physics for reducing operating temperatures and cesium plasma losses are being studied to achieve high reliability without sacrificing the power performance of the converters. Various cesium parameters which affect the converter performance are: (1) electron temperatures, (2) plasma ion densities, and (3) electric potential profiles. These were investigated using a Langmuir probe in a simulated converter. The parameters were measured in different cesium discharge modes.
Shimada, K.↗