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Employing the linearized hydrodynamic approach, the problem of coupling of electromagnetic energy to a one-dimensional inhomogeneous plasma bounded on one side by a metallic conductor is discussed in detail. The existence and effects of coupling of transverse electromagnetic and longitudinal plasma waves are explored. It is interpreted that under the influence of incident electromagnetic energy, the plasma sheath, when lossy, expands. It is shown that under some conditions a type of surface wave may be excited and also that in some cases a portion of the energy coupled to the plasma electrons is carried away when a (plasma) flow is present. [ABSTRACT FROM AUTHOR]

The paper is concerned with a theoretical study of photoconductive mixing phenomena. The output power at the difference frequency is obtained in terms of the applied optical input power, cavity shunt resistance and the physical properties of the semiconductor. The dependence on the length of the semiconductor is investigated and it is shown that a short length is preferable if WT is greater than 1 (=recombination time, =difference frequency). If is lesser than 1 the output power is found to be independent of length until the equivalent shunt resistance of the semiconductor becomes comparable with the shunt resistance of the cavity. [ABSTRACT FROM AUTHOR]

A method based on the paraxial ray equation is described for obtaining solutions to the equations of space-charge limited flow for electrostatic systems. According to usual practice any two parameters--voltage, curvature, and infinitesimal beam thickness--are prescribed along a central trajectory, and then the remaining parameters are found from the paraxial ray equation. The flow about the central trajectory is then found by solving for a curvilinear coordinate system satisfying the boundary conditions and with coordinate axes coinciding with the emitter and central trajectory. This is done by solving a set of ordinary differential equations derived from the paraxial ray equation. These are then combined according to a power series expansion to yield the complete flow solution anywhere along the central trajectory. The focusing electrodes are found by the method of analytic continuation. An ion propulsion gun designed by this method is described. [ABSTRACT FROM AUTHOR]

Study of the empirical relations between emission fields and gas discharge parameters indicated the possibility that atomic structure at least partially determined critical emission fields. The listing of all factors and the preparation of graphs point to what appears to be a close connection between the atomic number of a metal and its first critical emission field and its work-function.
The Millikan and Lauritsen empirical formula for emission field currents is derived. [ABSTRACT FROM AUTHOR]

A study has been made of some aspects of the disturbances often seen in moving striations in neon positive columns, using three tubes with different diameters. When the column contains cathode and anode sections, and both are not occupied by regular striations, the disturbances occur almost entirely in one section or the other, but not both. They start near the negative end of a section and move towards the positive end with velocity of the same order as that of ordinary positive moving striations. They could be eliminated from the anode section in the narrow tube by adjusting the length of the section to be an integral number of wavelengths of the positive striations and, in the wider tubes by increasing the current. The behavior of disturbances in the cathode section was studied in less detail. A comparison has been made between, the disturbance waves, and negative striations (Donahue and Dieke) and waves of stratification (Pekarek). [ABSTRACT FROM AUTHOR]

A frequency multiplier using an ' ideal ' non-linear capacitance, which may be approximated by a charge storage diode, is examined for the case where both the input and output circuits are tuned and where a finite resistance exists in series with the diode. After stating the problem in general terms, the case of a frequency doubler is examined and curves are given which relate the different circuit parameters and the drive conditions to the conversion efficiency and the output power. It is shown that high efficiencies (e.g. --2 d) may be obtained and that the converted power is considerably greater than for a varactor with the same bias voltage and total series resistance.
The theory is verified experimentally with a 3 Mc/6 Mc doubler and correlation with the theory is found to be good. [ABSTRACT FROM AUTHOR]

An iterative method of solution of the familiar Langmuir planar diode problem is formulated and solved analytically. By comparing the solution with the exact one, the speed of convergence of the method is determined. It is shown that this speed of convergence could be considerably increased by under-correcting the potential or current density on consecutive iterations. [ABSTRACT FROM AUTHOR]

A series of results are derived for some first-order statistics of stationary fading signals when the signal envelope has a Pearson distribution. In particular, expressions are found for the distribution of the instantaneous value of the signal, both in the absence and presence of additive gaussian noise, and for the noisy envelope distribution of the received waveform. These results are useful in the evaluation of the performance of receivers operating in an incoherent fashion on fading signals corrupted by gaussian noise. [ABSTRACT FROM AUTHOR]

The experimental determination of cross sections for some processes of inelastic collisions between electrons and atoms, molecules or ions, as for example excitation of electronic and vibration energy levels, excitation of ions, dissociation of molecules into neutral fragments and so on, is not yet solved satisfactorily.
We give in the present paper a suggestion for an experimental method which will make possible the measurement of these quantities. The possibilities of the proposed apparatus are analysed in detail. Special care is taken in the theoretical investigation of the analyser with which the measurements could be done. [ABSTRACT FROM AUTHOR]

The motion of electrons in a combined electric and magnetic field was investigated theoretically. The purpose of this investigation was to find out whether this special combined field can be used as an electron energy analyser of the kind necessary for inelastic cross-section measurements.
Very interesting cases of the electron motion can arise when various magnitudes of the magnetic field in the investigated structure are used. Some of them are discussed in the paper. [ABSTRACT FROM AUTHOR]