Astrophysical evidence for the direct electron- neutrino weak interaction.
Plasma neutrino process of Adams, Ruderman and Woo dependent on direct electron-neutrino interaction and connected with stellar evolution
Chin, C.-W.↗
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High-luminosity white dwarfs.
High luminosity white dwarfs possible evolution from planetary nebulae, discussing plasma neutrino processes
Chiu, H.-Y.↗
Ionization processes in mercury discharges
A summary of theoretical calculations of the ionization processes in mercury plasma is presented. Various possible ionization processes are analyzed and discussed. It is found that the ionization due to excited state interactions is dominant when the degree of ionization is small and that the ionization due to multistep electron impact is significant when the degree of ionization is high.
Wu, F. T.↗
Multitarget sequential sputtering apparatus
The development and characteristics of a sputtering apparatus are discussed. A potential difference is applied between the cathode and anode to produce a plasma for each target which is sputtered by accelerated ions within the plasma. The process of sputtering for various materials is described. Diagrams of the unit are provided.
Shima, R.↗
Theoretical models of magnetic field line merging. I
A review is presented of the models of magnetic field line merging defined as the process whereby plasma flows across a surface which separates regions including topologically different magnetic field lines. The models examined are characterized by uniform and antiparallel external magnetic fields. An attempt is made to simplify the presentation of the models, to clarify some doubtful mathematical points, or to extend the results to a different range of physical parameters. The models are described from a hydromagnetic point of view, with the configuration in any given case being determined by the boundary conditions. It is shown that the models developed by Sweet (1958), Parker (1957, 1963), Petschek (1964), Sonnerup (1970), and by Yeh and Axford (1970) are basically consistent, describing different aspects of the same problem; however, there is not a single model that would account for all the cases considered. The singular models and the compressible similarity models are physically not feasible.
Vasyliunas, V. M.↗
Abrasion-resistant coatings for plastic surfaces
Optically clear composition of organosilicon compounds insulates plastic surfaces and protects them from abrasion. Plasma polymerization process produces superior uniformity and clarity than previous coating techniques.
Wydeven, T.↗
Reconnexion
Reconnection is defined as the process whereby plasma flows across a surface that separates regions containing topologically different field lines. The magnitude of the plasma flow is a measure of the merging rate. Evidence for reconnection on the sun, in the solar wind, and in the magnetospheres of the terrestrial planets and Jupiter is briefly reviewed. Dependence of the merging rate on interplanetary conditions is discussed.
Russell, C. T.↗
Scratch resistant plastic lenses
Three-step plasma deposition process coats plastic lenses with strongly adhering scratch-resistant polymer film.
Kubacki, R. M.↗
A computer model of solar panel-plasma interactions
High power solar arrays for satellite power systems are presently being planned with dimensions of kilometers, and with tens of kilovolts distributed over their surface. Such systems face many plasma interaction problems, such as power leakage to the plasma, particle focusing, and anomalous arcing. These effects cannot be adequately modeled without detailed knowledge of the plasma sheath structure and space charge effects. Laboratory studies of 1 by 10 meter solar array in a simulated low Earth orbit plasma are discussed. The plasma screening process is discussed, program theory is outlined, and a series of calibration models is presented. These models are designed to demonstrate that PANEL is capable of accurate self consistant space charge calculations. Such models include PANEL predictions for the Child-Langmuir diode problem.
Cooke, D. L.↗
The simulation of the geosynchronous Earth orbit plasma environment in Chamber A: An assessment of possible experimental investigations
The possible use of Chamber A for the replication or simulation of space plasma physics processes which occur in the geosynchronous Earth orbit (GEO) environment is considered. It is shown that replication is not possible and that scaling of the environmental conditions is required for study of the important instability processes. Rules for such experimental scaling are given. At the present time, it does not appear technologically feasible to satisfy these requirements in Chamber A. It is, however, possible to study and qualitatively evaluate the problem of vehicle charging at GEO. In particular, Chamber A is sufficiently large that a complete operational spacecraft could be irradiated by beams and charged to high potentials. Such testing would contribute to the assessment of the operational malfunctions expected at GEO and their possible correction. However, because of the many tabulated limitations in such a testing programs, its direct relevance to conditions expected in the geo environment remains questionable.
Bernstein, W.↗
JT9D ceramic outer air seal system refinement program
The abradability and durability characteristics of the plasma sprayed system were improved by refinement and optimization of the plasma spray process and the metal substrate design. The acceptability of the final seal system for engine testing was demonstrated by an extensive rig test program which included thermal shock tolerance, thermal gradient, thermal cycle, erosion, and abradability tests. An interim seal system design was also subjected to 2500 endurance test cycles in a JT9D-7 engine.
Gaffin, W. O.↗
Broadband electrostatic noise and field-aligned currents in Jupiter's middle magnetosphere
Voyager 1 plasma wave observations have revealed the presence of an impulsive electrostatic emission localized to the Jovian middle magnetosphere that appears on the edges of the plasma sheet. This plasma mode has the same spectral and morphological characteristics of an emission that has been extensively studied in the earth's magnetosphere and has been associated with the presence of field-aligned currents. The results of a detailed study of the properties of this Jovian emission are presented by using comparisons with terrestrial observations as a basis for mode identification. The occurrence regions of the waves are compared with the measured magnetic field configuration to establish a correspondence with the plasma sheet. It is argued that this is a quasi-permanent global system of field-aligned currents linking the ionosphere of Jupiter to the middle magnetosphere, which powers energetic plasma heating processes occurring there. On the basis of knowledge of the consequences of field-aligned currents in the terrestrial magnetosphere, a scenario for acceleration/precipitation of inverted V electrons, concomitant aurorae, and energetic (approximately 10 keV) proton deposition into the middle magnetosphere resulting from field-aligned potential drops associated with this current system is suggested.
Barbosa, D. D.↗
The magnetic-anomaly model of the Jovian magnetosphere - A post-Voyager assessment
Predictions previously put forth (Dessler and Vasyliunas, 1979) as tests for the magnetic-anomaly model (in which the anomalously weak magnetic field region in the northern hemisphere of Jupiter influences the outer Jovian magnetosphere by one or more plasma interaction processes) are reexamined in the light of Voyager and other recent observations. With regard to the prediction of a restricted longitude range of enhanced interaction between Io and Jupiter's ionosphere, the longitudinal asymmetries seen both in ground-based observations of sulfur emissions from the Io torus and in Voyager observations of Jovian auroral emissions are found to agree well with the predicted asymmetries.
Vasyliunas, V. M.↗
Holes in the nightside ionosphere of Venus
Measurements of electron density and temperature by the Pioneer Venus orbiter electron temperature probe have been employed to examine the characteristics and morphology of ionospheric holes in the antisolar ionosphere of Venus. The holes apparently exist as north-south pairs which penetrate the ionosphere vertically down to altitudes as low as 160 km. Magnetic field measurements show that the holes are permeated by strong radial fields whose pressure is sufficient to balance the plasma pressure of the surrounding ionosphere. The electron temperature in the holes is substantially cooler than the surrounding ionosphere, except in the lowest density regions of the holes where the temperatures greatly exceed the ionosphere temperature. The low temperatures and the low densities of the holes are consistent with the strong radial magnetic fields which inhibit horizontal transport of plasma and thermal energy from the surrounding ionosphere. Plasma depletion processes associated with magnetotail electric fields may be important in the formation of the holes.
Brace, L. H.↗
The Origins of Plasmas in the Earth's Neighborhood (OPEN) program
The nature and objectives of the OPEN program are overviewed. The Origins of Plasmas in the Earth's Neighborhood program was conceived in 1979 and proposed as a major new initiative to study the energetics of the earth's space environment by the end of the 1980s. The objectives of OPEN have been integrated into the Global Geospace Study (GGS) segment to the International Solar-Terrestrial Physics (ISTP) program now being planned jointly by NASA, ESA, and Japan. The goals will be to develop a global understanding of the flow of energy from the sun through the earth's space environment above the neutral atmosphere and to define the cause and effect relationships between the plasma physics processes that link different regions of this dynamic environment. A network of four spacecraft will be used, each one carrying an instrument complement to characterize the composition and behavior of the upstream solar wind, the high-altitude polar magnetosphere, the equatorial magnetosphere, and the comet-like geomagnetic tail. Multispectral cameras will also be carried to image polar auroras at ultraviolet, visible and X-ray wavelengths. Experimentalists and theorists on the international team will participate.
Alexander, J. K.↗
Energy efficient engine high pressure turbine ceramic shroud support technology report
This work represents the development and fabrication of ceramic HPT (high pressure turbine) shrouds for the Energy Efficient Engine (E3). Details are presented covering the work performed on the ceramic shroud development task of the NASA/GE Energy Efficient Engine (E3) component development program. The task consists of four phases which led to the selection of a ZrO2-BY2O3 ceramic shroud material system, the development of an automated plasma spray process to produce acceptable shroud structures, the fabrication of select shroud systems for evaluation in laboratory, component, and CF6-50 engine testing, and finally, the successful fabrication of ZrO2-8Y2O3/superpeg, engine quality shrouds for the E3 engine.
Nelson, W. A.↗
Physics of the inner heliosphere 1-10R sub O plasma diagnostics and models
The physics of solar wind flow in the acceleration region and impulsive phenomena in the solar corona is studied. The study of magnetohydrodynamic wave propagation in the corona and the solutions for steady state and time dependent solar wind equations gives insights concerning the physics of the solar wind acceleration region, plasma heating and plasma acceleration processes and the formation of shocks. Also studied is the development of techniques for placing constraints on the mechanisms responsible for coronal heating.
Withbroe, G. L.↗
Development of a Global 3-D magnetohydrodynamic computational model for solar wind-cometary and planetary studies
The development of a global, 3-D magnetohydrodynamic computational model is described. This model is used to quantitatively describe the detailed continuum field and plasma interaction process of the solar wind with cometary and planetary magneto/ionopause shapes. The present solar wind/terrestrial planet interaction (Level 1) model (which is based on an axisymmetric gas dynamic plus frozen field approximation to the full MHD equations) is extended to a full 3-D gas dynamic (Level 2) approximation. A mass loading capability in the Level 1 interaction model is implemented.
Stahara, S. S.↗