Observation of closed loops in high-voltage discharges: a possibleprecursor of magnetic flux trapping

In multimegavolt electrostatic generators, the accidental sparkover discharges change in character as the voltage and stored energy increase. The usual forked, unidirectional discharges are replaced by complex discharges containing numerous closed loops. It is suggested that this is an example of the formation of closed-current loops that generate magnetic fields in astrophysics     

Microwave frequency shifting using photon acceleration

Using a Bostick Gun as a plasma source, we have been investigating the effects of a moving plasma front on the frequency of an incident R.F. signal. We have been able to measure frequency shifts of 10 MHz frequency with a 2.6 GHz signal. The density is such that the plasma frequency is well above the transmitter frequency 1.3 meters from the plasma source. No magnetic field is used.     

An enhanced ionizer

Corona discharges in the air are intensified if a small amount of nonelectronegative gas is fed into the limited region around each corona point. The ions produced in the active region then migrate into the air, to produce an intensified negative and positive ion plasma     

Landau Growth for Students Part I Initial Valuie Problem

This paper is internded to demonstrate to students that electron Landau growth of plasma waves is an easily understood and computed phenomenon. This derivation does not use the usual Fourier-Laplace transform technique with the inversion and final result being obtained by contour integration and residue theory. Instead, a simple treatment, following the original work of Vlasov, is used. Landau's original solution is recovered both for growth and decay, but only the growing part rigorously satisfies the initial assumptions.     

Reflection and Transmission of Ion Acoustic Waves from a Plasma Discontinuity

We calculate transmission and reflection coefficients for an ion acoustic wave incident from the upstream direction upon a plasma discontinuity of width much less than the wavelength. In the limit of an infinitely strong discontinuity there is complete in phase reflection.     

Spark Breakdown - An Electrostatic Criterion

This paper examines one basic process causing the d. c. high voltage breakdown of a gas. Specifically, it contains a modified criterion for the transition of a Townsend Avalanche to a Streamer Discharge. Instead of the assumption that the electrons in the avalanche are spread laterally by multiple scattering on gas molecules (thermal diffusion), the assumption used is that the electrons are spread solely by mutual electrostatic repulsion. A criterion is found that yields quantitative results comparable to those obtained using the "multiple scattering" assumption. This modified criterion is probably most useful where "multiple scattering" is improbable - where an electron loses almost all of its energy on colliding with complex gas molecules. In addition, the classical (thermal-diffusion-dominated) breakdown criterion is re-derived in a much simpler form.     

On Electron Acceleration by Electric Field

Critical electric fields have been derived above which electrons are freely accelerated overcoming electrostatic instabilities driven by electron current. Two-stream instability and trapped particle instability are considered as the major drag effects on electrons.     

Disproof of Cowling's theorem

T.G. Cowling's theorem (1934) is a general statement that axisymmetric dynamos cannot be constructed in astrophysical bodies. The theorem is based on the assumption that the electrical conductivity is a scalar, σE=J. In a counterargument, the author demonstrates that this statement is not valid for a diffuse plasma. He suggests that, in an astrophysical plasma, collisional processes can violate Cowling's theorem by scattering current into a current-free channel