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The frequency of plane standing waves of electrons moving through a background of infinitely heavy ions is strictly independent of amplitue as long as the electron velocity is a unique function of position. This result is contrary to those presented in recent publications by S. Amer, J. Electronics and Control, 5:105-13, 158 and L. Gold, J. Electronics and Control, 6:548-549, 1959. The frequencies of spherical and cylindicl plsma oscillations, however, do depend upon the amplitude of the oscillation. AsA RESULT, ANY PHASE RELATIONSHIP BETWEEN ELECTRONS EVENTUALLY WILL BE DESTROYED AND THE ELECTRON VELOCIY BECOMES MULTIVALUED. Therefore steady free oscillations do not persist even in a cold plasma. (Author)

An investigation was made of the signal spreading through a uniform hot electron plasma from a source which is localized in space and in time. In other words, we construct the Green's function describing electrostatic events in plasmas. (Author), Presented at the Annual Meeting of the American Physical Society, Plasma Physics Division (7th), San Francisco, Calif., 8-11 Nov 65.

The objective of this study is to develop and explore new methods and principles in the areas of electron and wave interaction and microwave tubes for the generation, amplification, modulation, and detection of microwave signals leading to the solution of current and future problems in the development of radar, communications, and electronic countermeasures system. (Author)

The report describes studies which established the existence of Landau damped longitudinal space-charge waves in our thermionic sodium plasma tube. Good agreement was found between the measurements and the theoretical dispersion relation predicted by Landau. (Author), See also Quarterly status rept. no. 8, AD-687 113 and Quarterly status rept. no. 10, AD-687 115.

The theoretical study of electrostatic waves was extended to include the finite extent of the plasma and external boundries. The plasma capacitor problem is presented to illustrate the effect of multiple reflections from the boundries. We show that only weak relfections are set up between open circuited grids. The normalized voltage transfer ratio is calculated for six different grid arrangements of double and triple grids. We operated the sodium plasma tube for two months and made DC density measurements which agreed with theoretical predictions. Noise measurements showed that no instabilities are present in our plasma and thereby we conclude that our plasma forms an excellent environment for electrostatic wave experiments. (Author), See also Quarterly status rept. no. 7, AD-629 496 and Quarterly status rept. no. 9, AD-687 114.

The floating potential of a probe in a high density seeded plasma is described with the classical electrostatic probe theory extended to include emission. In general, this emission consists of ions, atoms, and electrons. The rate at which these particles are emitted depends on the probe tempera- ture and on its surface coverage by the seed. Since the ion arrival is gov- erned by how the surface floats electrically with respect to the plasma, a coupled situation can exist. The problem in formulated in terms of two-temperature description where plasma electrons retain their temperature as they approach the surface. The theory is developed in general for probes biased to a surface where emission conditions can be known, and then it is specialized to catalytic and noncatalytic surfaces. The noncatalytic situation is correlated with some data for an atmospheric argon plasma seeded with potassium. A computational scheme is used to calculate the equilibrium fluxes from a surface which is absorbing seed.