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Report presents new theory of analytic functions of three-dimensional complex variables. While three-dimensional system subject to more limitations and more difficult to use than the two-dimensional system, useful in analysis of three-dimensional fluid flows, electrostatic potentials, and other phenomena involving harmonic functions.
The results of verification testing under NASA Contract NAS9-17249 are summarized in this Final Report. An Appendix is published separately. The report contains a brief discussion of design elements, test results, and a discussion of the latter. The contract was awarded for development and demonstration of design modifications to the NASA Standard Initiator-1 (NSI-1), resulting in the development of NSI-2. The intent of the project was to develop and prove the following design features: (1) Protection from premature initiation due to electrostatic potential by means other than a spark gap; (2) Development of an integral insulated charge cup for use with a zirconium/potassium perchlorate type mixture; (3) Improved cost and reliability figures by the use of a deposited ridge; and (4) Elimination of dudding as a result of the pyrotechnic shock effect, the movement of the primer composition away from the bridge circuit.
This is the Appendix to the Final Report on the results of verification testing on NASA Contract NAS9-17249. The test results are presented graphically in the Appendix. The Final Report is a brief discussion of design elements, test results, and a discussion of the latter. The contract was awarded for development and demonstration of design modifications to the NASA Standard Initiator-1 (NSI-1), resulting in the development of NSI-2. The intent of the project was to develop and prove the following design features: (1) Protection from premature detonation due to electrostatic potential by means other than a spark gap; (2) Development of an integral insulated charge cup for use with a zirconium/potassium perchlorate type mixture; (3) Improved cost and reliability figures by the use of a deposited bridge; and (4) Elimination of dudding as a result of the pyrotechnic shock effect, the movement of the primer composition away from the bridge circuit.
The possibility that at least some astrophysical jets are initially electromagnetic in origin is examined. Subsequent pick-up of ionization would convert such electromagnetic jets into hydrodynamic jets. In such a model, relativistic outflow is formed into highly collimated beams simply through the interaction with the surrounding medium. Forming jets under such general circumstances is encouraging in view of the range of scales that appear to be involved. The overall properties of such jets are largely determined by a single dimensionless parameter: the characteristic electrostatic potential drop rewritten as a particle Lorentz factor. Consequently, the determination of any one observable, such as the total power output, also determines the particle energy scale, the electromagnetic field strengths, etc.
The first numerical simulations of the nonlinear evolution of the electrostatic Kelvin-Helmholtz (K-H) instability with ionospheric Perderson conductivity coupling are presented. It is found that the K-H instability develops in a distinctly different manner in the nonlinear regime with Pedersen coupling than without it. Pedersen coupling effects, in conjunction with a neutral wind and density gradient, are shown to result in an increased time scale for K-H instability wave growth, to inhibit K-H vortex formation, to lead to nonlinear structures which can be described as 'breaking waves', and to generate, in the nonlinear regime, small-scale turbulence by means of secondary instabilities growing on primary waves. The spatial power spectra of the electrostatic potential and density fluctuations are computed, and differences with and without Pedersen effects are reported.
ISEE-1 energetic ion distributions are compared with previously published lower-energy ISEE-1 H(+) and He(2+) distributions in the quiet-time plasma sheet at about 15 earth radii and within about 1 earth radius of the expected neutral sheet position. Although moment calculations performed over the nearly isotropic H(+) and He(2+) plasma distributions yield low bulk velocities of less than 14 km/s, the spectral shapes of these signatures are indicative of high flow speeds. It is suggested that H(+) and H(2+) ions of solar wind origin were accelerated through an electrostatic potential of about 2.4 kV prior to the ISEE-1 observations in the plasma sheet on a closed magnetospheric field line, and that a second plasma sheet population existed at this ISEE-1 position in the geomagnetic field.
A new quasi-thermal trap model of solar flare hard X-ray bursts is presented. The new model utilizes the trapping ability of a magnetic mirror and a magnetic field-aligned electrostatic potential produced by differences in anisotropies of the electron and ion distribution function. It is demonstrated that this potential can, together with the magnetic mirror itself, effectively confine electrons in a trap, thereby enhancing their bremsstrahlung yield per electron. This analysis makes even more untenable models involving precipitation of the bremsstrahlung-producing electrons onto a cold target.
The ion two-stream instability develops between upflowing H(+) and O(+) in the auroral acceleration region, if the two species are accelerated to different velocities in a semistationary electrostatic potential. Parallel propagating modes are unstable only for small relative drifts, while oblique modes remain unstable at larger drifts and, consequently, higher altitudes. The effects of oblique modes on ion heating are investigated, and it is found that O(+) heats primarily by trapping in the direction of wave propagation during the early, coherent phase of wave growth in the temporal evolution problem. After undergoing trapping along the magnetic field direction, H(+) heats primarily by quasi-linear diffusion when the spectrum broadens nonlinearly. The parallel ion distributions evolve by formation of a high-energy (low-energy) tail on oxygen (hydrogen) along with bulk slowing of hydrogen, which results in more energetic oxygen than hydrogen. Total heating is greatest in the direction of wave propagation, and this effect is greater for hydrogen than for oxygen.
The present use of the Rice convection model to investigate the electrodynamic coupling of the thermosphere to the inner magnetosphere encompasses the effects of EUV-driven and convection-driven neutral winds under quasi-equilibrium conditions. Convection-driven winds are included self-consistently and interactively; a steady-state wind parameterization is written analytically in terms of the electrostatic potential, which is in turn included in a closed-loop calculation for the electric potential itself. The simulations conducted show that, as the neutral system approaches a quasi-equilibrium state, the neutral winds play a much more significant role.
A simple model is constructed for the electric fields in the collapsing wave packets found in 3D simulations of driven and damped isotropic strong Langmuir turbulence. This model, based on a spherical-harmonic decomposition of the electrostatic potential, accounts for the distribution of wave-packet shapes observed in the simulations, particularly the predominance of oblate wave packets. In contrast with predictions for undamped and undriven subsonic collapse of scalar fields, oblate vector-field wave packets do not flatten during collapse but, instead, remain approximately self-similar and rigid.
The present investigation of three-dimensional reconnection of magnetic fields with nulls and of fields with closed lines gives attention to the geometry of the former, with a view to their gamma-line and Sigma-surface structures. The geometric structures of configurations with a pair of type A and B nulls permit reconnection across the null-null lines; these are the field lines which join the two nulls. Also noted is the case of magnetostatic reconnection, in which the magnetic field is time-independent and the electrostatic potential is constant along field lines.
Variations of thermal electron parameters in the solar wind are studied at heliocentric distances from 0.3 to 1 AU using Helios data from 1974 to spring 1976 just before solar minimum. Consideration is given to variations across plasma streams and across the sector structure of the IMF. It is found that, in high-speed streams in the interior of magnetic sectors, the electron temperatures are relatively low and strongly anisotropic. The electron temperatures become larger and less anisotropic toward sector boundaries in the slow solar wind. Radial gradients for the thermal electron parameters and polytrope indices for the core temperatures and electron temperatures are studied. Evidence is presented that the electrons in high-speed streams are heated by external heat sources. Interplanetary electrostatic potential differences caused by the thermal electron pressure gradients are estimated to be between 30 and 90 V.
A two dimensional numerical model of the inversion layer metal insulator semiconductor (IL/MIS) solar cell is proposed by using the finite element method. The two-dimensional current flow in the device is taken into account in this model. The electrostatic potential distribution, the electron concentration distribution, and the hole concentration distribution for different terminal voltages are simulated. The results of simple calculation are presented. The existing problems for this model are addressed. Future work is proposed. The MIS structures are studied and some of the results are reported.
The authors experimentally identified three distinct regimes with large differences in current collection in the presence of neutrals and weak magnetic fields. In magnetic field/anode voltage space the three regions are separated by very sharp transition boundaries. The authors performed a series of laboratory experiments to study the dependence of the region boundaries on several parameters, such as the ambient neutral density, plasma density, magnetic field strength, applied anode voltage, voltage pulsewidth, chamber material, chamber size and anode radius. The three observed regimes are: classical magnetic field limited collection; stable medium current toroidal discharge; and large scale, high current space glow discharge. There is as much as several orders of magnitude of difference in the amount of collected current upon any boundary crossing, particularly if one enters the space glow regime. They measured some of the properties of the plasma generated by the breakdown that is present in regimes II and III in the vicinity of the anode including the sheath modified electrostatic potential, I-V characteristics at high voltage as well as the local plasma density.
This paper describes electron data obtained during the Neptune encounter by the Voyager 2 plasma science experiment. The densities and temperatures of low-energy (10-5950 eV) electrons and the electrostatic potential of the spacecraft near Neptune are derived. The data indicate that the escape of charged particles from Triton and the local ionization of atoms in the neutral torus originating from Triton are the major plasma sources. It is inferred that this neutral torus of hydrogen atoms has a density of about 300/cu cm and an inner boundary at 8 R(N). The data near Neptune exhibit signatures suggesting that both precipitation into Neptune's atmosphere and ring absorption are important plasma loss mechanisms. Plasma transport in the magnetosphere appears to be very fast; the diffusion coefficient is 1 x 10 exp -7 L exp 3 R(N) exp 2/sec.
Calculations have been performed which encompass both a self-consistent ion source extraction plasma sheath and the primary ion optics including sheath and electrode-induced aberrations. Particular attention is given to the effects of beam space charge, accelerator geometry, and properties of the downstream plasma sheath on the position of the electrostatic potential saddle point near the extractor electrode. The electron blocking potential blocking is described as a function of electrode thickness and secondary plasma processes.
Preliminary work in the investigation of electron injection and acceleration at parallel shocks is presented. A simple model of electron heating that is derived from a unified shock model which includes the effects of an electrostatic potential jump is described. The unified shock model provides a kinetic description of the injection and acceleration of ions and a fluid description of electron heating at high Mach number, supercritical, and parallel shocks.
Measurements indicative of incipient lightning yield additional information. New instrument gives reliable readings. High-voltage ac bias applied to needle point through high-resistance capacitance network provides corona discharge at all times, enabling more-slowly-varying component of electrostatic potential of needle to come to equilibrium with surrounding air. High resistance of high-voltage coupling makes instrument insensitive to wind. Improved corona-point instrument expected to yield additional information assisting in safety-oriented forecasting of lighting.