Electric Field In Vacuum Research Articles

An experimental investigation of the end-hat effects in a crossed-field amplifier via three-dimensional electron density measurements

In situ three-dimensional electron density profile measurements have been made for the first time to study the end-hat space-charge region in a crossed-field amplifier. It has been found that a separated electron population exists in that region and is detached from the main beam when the end-hats are biased positively with respect to the sole. An investigation into the vacuum electric field profile and the overall device performance versus end-hat bias has suggested that such an electron population may be caused by a redistribution of the beam electrons by the axial and radial end-hat electric field. >

Influence of Radius of Curvature, Contact Angle and Material of Solid Insulator on the Electric Field in Vacuum (and Gaseous) Gaps

The insulation strength of a vacuum gap bridged by a solid insulator is lower than that in the absence of the solid insulator. The triple junction formed by the solid insulator, electrode, and vacuum in vacuum devices (or a gas in high-pressure apparatus) has a critical influence on the withstand voltage level of the insulating gap. The electric field is calculated using the charge simulation technique at the triple junction as a function of the junction geometry. The dependence of the field is studied for a varying contact angle a between the solid insulator and the electrode in the range 0 to 90°, for a varying ratio r/D of the radius of curvature r of the rounded edge of the solid insulator at the junction to the length of the insulator D, at a fixed r/D and varying r and D and for different practical insulator materials having relative dielectric permittivities ε£ in the range 2.1 to 12000. It has been found that the electrical field at the electrode-solid insulatorvacuum junction has a strong dependence on both the contact angle and the solid insulator material. The tangential and normal components of the electric fields are determined at the solid insulator-vacuum boundary and away from the boundary both inside the solid insulator and in the vacuum. Large enhancements in the electric field at the triple junction are found. The effects of the parameters α, r, and εr on the with-stand voltage of the insulating gap are discussed.

イオンプレーティング法の工学的応用に関する研究

Ion plated film has good properties, that is, a good adherence onto the substrate, a high strength of the film and a film formation all over the surface without rotation or inclination of the substrate, because ion plating is the new technique by which ions are deposited onto the substrate under the electric field in vacuum. So, it is easily imagined that ion plating technique can be applied to technology at wide region, e.g. application to tribology and strengthening of the materials. In the present research, an ion plating apparatus with the sputtering technique, which can be applied to refractory materials and chemical compounds, was developed, and tensile tests of the advanced filaments covered with B4C, Cu, and Ti films were performed with an Instoron tensile testing machine. The results of the tensile tests reveal that the proportional limit and tensile strength of the stainless steel covered with B4C increased up to about 133 % and 126% respectively. Also discussions were made about disruption of advanced filaments with a SEM.

A new pulsar atmospheric model. I - Aligned magnetic and rotational axes

A model is proposed for the plasma atmosphere about a rotating magnetized neutron star with aligned magnetic and rotational axes. The model is generated with the aid of a gedanken experiment in which the rotational velocity ..cap omega.. of the star is adiabatically increased. By this device it is established that the star will acquire a charge sufficient to stop the charge loss to the nebula, but not the local surface emission. The resulting monopole electric field causes plasma to flow across magnetic surfaces at large distances from the star, where it dominates the dipole magnetic field, thereby forming a current loop from the polar caps to polar annuli. This same electric flow region can also establilsh current loops to the nebula, provided electron-positron pairs are produced. The vacuum electric field has a surface where ExB=0, which is a dome over the polar cap. For larger ..cap omega.., radiation losses cause beam particles to be trapped around this surface, forming a relatively stationary, possibly turbulent component of the atmosphere. It is shown that this plasma dome is more stable than the force-free atmosphere, and is therefore presumably maintained by a balance between the radiative capture and diffusion of particles backmore » to the star. A small toroidal, nearly force-free region consisting of opposite charges also exists near the equator and is attached to an equatorial disk, maintained by diffusion. The limited atmospheric extent and toroidal drift velocity suggest that all the magnetic surfaces are closed (near-dipolar). (AIP)« less

Electron-beam spreading and its effect on sustainer current and field distribution in CO2 lasers

An electron-beam-initiated high-pressure CO2 laser discharge is investigated. It is assumed that initially the discharge current flows along the vacuum electric field direction. The resulting distortion of the electric field is calculated by a linearization of the continuity equation. We have computed the solution for the special case of a finite electron beam and infinite planar electrodes. The predicted variation of the sustainer current and distortions of the applied voltage are compared with experimental results.

Gas extraction from the surface of an insulator in a strong electric field in vacuum: A A Avdienko and A V Kiselev, Zh Tekh Fiz, 37 (3), March 1967, 533–537 (in Russian)

Gas extraction from the surface of an insulator in a strong electric field in vacuum: A A Avdienko and A V Kiselev, Zh Tekh Fiz, 37 (3), March 1967, 533–537 (in Russian)