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Performance of plasma source operated with helium - intensity and temperature profiles of source electronic instrumentation for detecting weak spectrum lines
Stark broadening of singly ionized argon lines in helium-argon plasma behind reflected shock wave in electromagnetic T tube with backstrap
Line broadening of triplet diffuse series of helium in arc-jet plasma
Refractive index computation for free electrons and neutral atoms in cesium plasma at helium neon laser wavelengths
The observations of solar wind helium enhancements following major solar flares are reviewed, and the hypothesis that helium enhancements often mark flare piston plasma is confirmed. Helium enhancements were observed during each of the three periods (March 1966, July 1966, August/September 1966) of major solar activity that occurred from October 1965 to October 1966. No enhancements were seen during the long quiet periods that occurred that year. At 1 AU, the helium-enhanced plasma pistons had slowed so that the velocity was 80 percent of the mean transit velocity, in general agreement with theoretical models of the propagation of flare disturbances. A qualitative model, in which the piston plasma is accelerated from the flare site deep in the corona, is discussed briefly. If the model is valid in general outline, the piston plasmas provide samples of material from the lower levels of the corona.
To improve nanotube production, we developed a novel optical control technique, based on the shape of the visible plasma zone created between the anode and the cathode in the direct current (DC) arc process. For a given inert gas, we adjust the anode to cathode distance (ACD) in order to obtain strong visible vortices around the cathode. This enhance anode vaporization, which improve nanotubes formation. In light of our experimental results, we focus our discussion on the relationship between plasma parameters and nanotube growth. Plasma temperature control during arc process is achieved using argon, helium, and their mixtures as a buffer gases. The variation of the gas mixture from pure argon to pure helium changes plasma temperature. As a consequence, the microscopic characteristics of nanotubes as diameter distribution is changed moving from smaller values for argon to higher diameters for helium. We also observe a dependence of the macroscopic characteristics of the final products as Brunauer-Emmett-Teller (BET) surface area.
Recombination rate of electrons in high pressure helium-like plasma with gas temperature fixed at 300 K and electron temperature varied between 300-2000 K
Modes of Kadomtsev plasma instability in helium positive column, noting diffusion loss
Saturation induced optical nonreciprocity in He-Ne ring laser plasma, eliminating frequency locking by using Faraday effect
New observations of particle and wave data from the magnetic equator from the DE 1 spacecraft are reported. The results demonstrate that the equatorial plasma population is predominantly hydrogen and that the enhanced ion fluxes observed at the equator occur without an increase in the total plasma density. Helium is occasionally found heated along with the protons, and forms about 10 percent of the equatorially trapped population at such times. The heated H(+) ions can be characterized by a bi-Maxwellian with kT(parallel) = 0.5-1.0 eV and kT = 5-50 eV, with a density of 10-100/cu cm. The total plasma density is relatively constant with latitude. First measurements of the equatorially trapped plasma and coincident UHR measurements show that the trapped plasma is found in conjunction with equatorial noise.
General atom theory for volume ion production cost and rate in tenuous plasma having Maxwellian distribution of electron energies - detailed results for argon, cesium and helium gases
Theory of low energy positron helium scattering below positronium threshold - adiabatic method applied
Evolution of 5 solar masses star model from main sequence through core helium burning compared to 3 solar masses model, noting Hertzsprung-Russell diagram
Evolution of 9 solar masses stellar model of population I initial composition from main sequence through core helium burning
Configuration interaction in helium continuum between first and second quantum thresholds
Helium RF discharge radiation temperature as magnetic field function measured, discussing enhanced diffusion role in radiation temperature determination
Nonlinear effects of recombination and collective diffusion associated with nuclear seeded plasmas using helium isotopes in gas cooled reactors
Detailed information on the spacecraft performance, mission operations, and tracking and data acquisition is presented for the Mariner Venus 1967 and Mariner Venus 1967 extension projects. Scientific and engineering results and conclusions are discussed, and include the scientific mission, encounter with Venus, observations near Earth, and cruise phase of the mission. Flight path analysis, spacecraft subsystems, and mission-related hardware and computer program development are covered. The scientific experiments carried by Mariner 5 were ultraviolet photometer, solar plasma probe, helium magnetometer, trapped radiation detector, S-band radio occultation, dual-frequency radio propagation, and celestial mechanics. The engineering experience gained by converting a space Mariner Mars 1964 spacecraft into one flown to Venus is also described.