Some studies of whistler mode amplification.
Whistler mode transverse electromagnetic plasma wave interaction with monoenergetic gyrating electron beam, noting instabilities and relevance to whistler amplification
Crawford, F. W.↗
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Results for “plasma interactions”
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 pulsar emission mechanism
Interaction of plasma discontinuities in pulsar emission mechanism
Michel, F. C.↗
A Faraday rotation measurement of a 13-cm signal in the solar corona
Faraday rotation measurement of 13 cm telemetry carrier wave interacting with plasma and magnetic field in solar corona
Stelzried, C. T.↗
Factors in the electrostatic equilibration between a plasma thrust beam and the ambient space plasma
Electric propulsion plasma thrust beam and ambient space plasma electrostatic equilibration, considering various charged particle parameters involved in bi-plasma system interactions
Cole, R. K.↗
Design of the particles experiment subsystem of the Apollo lunar subsatellite.
In August 1971 an eighty pound subsatellite was ejected from Apollo 15 into lunar orbit. The subsatellite is expected to remain in lunar orbit for at least one year. The Particles Experiment Subsystem of the subsatellite was designed to implement the Particle Shadows/Boundary Layer Experiment. The objective of the experiment is to obtain data for the study of the formation and the dynamics of the earth's magnetosphere, the interaction of plasmas with the moon, and the physics of solar flares. The design of the particle detector telescopes is considered together with details of collimator design, silicon detectors, the absorber foil, and the power subsystems. The instrument performance in lunar orbit is discussed.
Baum, J. J.↗
Theoretical and experimental studies of the nature and characteristics of space related plasma resonance phenomena
Theoretical and experimental studies of space related plasma wave propagation and resonance phenomena cover whistler emissions and instabilities, low frequency plasma instabilities, nonlinear wave interactions and scattering from plasma column, and the resonance come of dipole antenna immersed in cold overdense magnetoplasma.
Crawford, F. W.↗
Electromagnetic instabilities in non-uniform anisotropic plasmas
The mechanisms of electromagnetic instabilities in nonuniform plasmas are analyzed, taking into account the anisotropy in temperature and temperature gradients. It is shown that resonance-type drift instabilities can be produced in nonuniform plasmas by resonant interactions between ions or electrons and plasma drift waves when the temperature anisotropy and temperature gradients vary widely. In contrast, production of off-resonance type instabilities is found to be possible only when the temperature gradients are much greater than the magnetic field gradients. It is pointed out that these findings are applicable to solar wind plasmas with hydromagnetic instabilities and shock transition regions. Attention is given to the occurrence of resonance ion instabilities and off-resonance drift cyclotron instabilities in the solar wind.
Buti, B.↗
Study of cosmic ray motion in cosmic space near the earth
Data are presented on experimental installations developed in the cosmic ray variations laboratory in Kazgu (Alma-Ata). Various experiments on modelling the interaction of plasma with the geomagnetic field as well as the plasma distribution in quiet and disturbed fields are described. The characteristics of the meson supertelescope using scintillators (effective area, 10 sq m) for vertical alignments designed to study microvariations of the cosmic rays and their interrelation with magnetospheric fluctuations and the study of solar wind parameters are given.
Budilov, V. K.↗
Analysis of data from the Lockheed Experiment on ATS-5
Satellite observations of auroral electrojets, electron fluxes, and magnetic storm activity are presented and discussed. Plasma-particle interactions are examined for the earth's magnetosphere, and data (i.e., magnetograms) of the satellite observations are analyzed.
Sharp, R. D.↗
Torquing and electrostatic deformation of the solar sail
The impact of natural sources of electrical-mechanical oscillations induced by the environment on the solar sail system is evaluated. The study indicates that, to the level of accuracy (first order) of the analysis, none of the natural sources studied, which range from plasma wave interactions to E x B forces, will have a significant impact on the proposed solar sail design. The study is not intended as an exhaustive analysis, and further analysis, particularly in the area of artificially induced oscillations, is needed.
Laquey, R. E.↗
Neutrino, gamma-ray, electron, and positron production in an ultrarelativistic plasma
Neutrino, gamma-ray, electron and positron production resulting from inelastic proton-proton collisions in a highly relativistic plasma such as may exist in extragalactic radio or gamma-ray burst sources is examined. The source functions of primary (pions, kaons, and neutrons) and secondary (photons, electrons, positrons and neutrinos) products of relativistic nuclear collisions are computed for the cases of power law and Maxwellian relativistic proton distributions. It is shown that in plasma which is optically thin to interactions between the plasma and secondary gamma-rays, electrons and positrons, only a small fraction of the initial energy is emitted in the observable form of neutrinos and gamma rays. In an optically thick plasma on the other hand, most of the energy of the relativistic protons is found to be equally divided between gamma rays and neutrinos, although only the neutrinos may escape freely to be observed.
Marscher, A. P.↗
About the parametric interplay between ionic Mach number, body-size, and satellite potential in determining the ion depletion in the wake of the S3-2 satellite
The variation of ion current depletion in the wake of the U.S. Air Force satellite S3-2 is quantitatively determined, taking into account altitudes in the range from 300 to 1100 km. The considered investigation has the objective to present results which besides of being of scientific interest per se are useful to the planning of future experiments of body-plasma electrodynamic interactions in a supersonic and sub-Alfvenic flow regime to be conducted on board the Shuttle/Spacelab. More specifically, it is expected that the outcome of investigations of the kind presented will be useful in the planning of instrument location on ejectable ensembles of probes and on the Orbiter itself in future Shuttle/Spacelab missions.
Samir, U.↗
Turbulence and wave particle interactions in solar-terrestrial plasmas
Theoretical modelling of two dimensional compressible convection in the Sun shows that convective flows can extend over many pressure scale heights without the nonlinear motions becoming supersonic, and that compressional work arising from pressure fluctuations can be comparable to that by buoyancy forces. These results are contrary to what was supposed in prevailing mixing length models for solar convection, and they imply a much greater degree of organized flow extending over the full depth of the convection zone. The nonlinear penetration of motions into the stable region below the convection zone was emphasized. These compressible flows are dominated by downward directed plumes in the unstable zone. Their strong penetration into the region of stable stratification below excites a broad spectrum of internal gravity waves there, and these in turn feed back upon the convection in the unstable zone to produce a rich time dependence.
Dulk, G. A.↗
Turbulence and wave particle interactions in solar-terrestrial plasmas
Activities in the following study areas are reported: (1) particle and wave processes in solar flares; (2) solar convection zone turbulence; and (3) solar radiation emission. To investigate the amplification of cyclotron maser radiation in solar flares, a radio frequency. (RF) heating model was developed for the corona surrounding the energy release site. Then nonlinear simulations of compressible convection display prominent penetration by plumes into regions of stable stratification at the base of the solar convection zone, leading to the excitation of internal gravity waves there. Lastly, linear saturation of electron-beam-driven Langmuir waves by ambient density fluctuations, nonlinear saturation by strong turbulence processes, and radiation emission mechanisms are examined. An additional section discusses solar magnetic fields and hydromagnetic waves in inhomogeneous media, and the effect of magnetic fields on stellar oscillation.
Dulk, G. A.↗
Effect of argon and hydrogen on deposition of silicon from tetrochlrosilane in cold plasmas
The roles of Ar and H2 on the decomposition of SiCl4 in cold plasma were investigated by Langmuir probes and mass spectrometry. Decomposition of the reactant by Ar only has been found to be very slow. In presence of H2 in the plasma SiCl4 is decomposed by fast radical-molecule reactions which are further enhanced by Ar due to additional ion-molecule reactions in which more H radicals are produced. A model for the plasma-surface interactions during deposition of mu-Si in the Ar + H2 + SiCl4 system is presented.
Manory, R. R.↗
Planetary science
The following types of experiments for a proposed Space Station Microgravity Particle Research Facility are described: (1) low velocity collisions between fragile particles; (2) low velocity collisions of ice particles; (3) plasma-dust interaction; and (4) aggregation of finely-comminuted geological materials. The required capabilities and desired hardware for the facility are detailed.
Marshall, John R.↗
The contribution to the gamma-ray background from a superposition of 3C 273-like jet sources
Recent theories suggest that quasar jets may produce the gamma-ray emission observed in sources such as 3C 273. One of these theories is tested to see if it is consistent with observations of the gamma-ray background. Quasar jets are taken as the source of this radiation, each with the spectrum of the nearby quasar 3C 273, and with an evolution in time based on a model for the observed gamma-rays of 3C 273. In that model, a plasma jet interacts with the ambient intergalactic gas to produce (from nuclear collisions) secondary electrons which lead to isotropic bremsstrahlung gamma-rays, and ultimately to a double radio source. It is shown that the gamma-ray background can be modeled in general as a superposition of such discrete sources of various redshifts. The results are consistent with the observed background intensity and spectral form; of course, there are uncertain and adjustable parameters.
Sadun, Alberto C.↗
Computer modeling of current collection by the CHARGE-2 mother payload
The three-dimensional computer codes NASCAP/LEO and POLAR have been used to calculate current collection by the mother payload of the CHARGE-2 rocket under conditions of positive and negative potential up to several hundred volts. For negative bias (ion collection), the calculations lie about 25 percent above the data, indicating that the ions were less dense, colder, or heavier than the input parameters. For positive bias (electron collection), NASCAP/LEO and POLAR calculations show similar agreement with the measurements at the highest altitudes. This agreement indicates that the current is classically magnetically limited, even during electron beam emission. However, the calculated values fall well below the data at lower altitudes. It is suggested that beam-plasma-neutral interactions are responsible for the high values of collected current at altitudes below 240 km.
Mandell, M. J.↗