Vacuum discharge effects in the diodes of high-current electronaccelerators

The processes occurring in the diodes of high-current electron accelerators which affect the electron beam structure are discussed. Two types of diodes are analyzed: planar diodes producing large cross-section beams, and magnetically insulated diodes producing cylindrical beams. The effects considered are: the screening effect, the effect of touches, the relay effect, the ring effect, etc. They are entirely associated with the explosive electron emission occurring on the cathode of a high-current diode. Methods which can be employed to eliminate or control some of these effects are described-namely, the application of an additional magnetic field, artificial initiation of emission centers, and employment of metal-dielectric cathodes. Examples of several types of cathode are given     

Volume discharge excited by an electron beam in an Ar-SF6 mixture I. Beam-controlled discharge

Beam-controlled current flow is investigated in an Ar-SF₆ mixture at atmospheric pressure. It is shown that electron attachment to SF₆ molecules plays an important role in the charge-dparticle balance, and the attachment constant is determined. The discharge energy properties are studied.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 72–76, July, 1978.     

Study of the pd reaction at ultralow energies using hydrogen liner plasma

The pd reaction (pd → He + γ (5.5 MeV)) is studied in the astrophysical energy collision range of protons with deuterons using the hydrogen liner in the inverse Z-pinch configuration at the pulsed power generator MIG (HCEI, Tomsk). Fundamental characteristics of this and other light-nucleus reactions at ultralow energies are important for problems of basic physics and astrophysics. The knowledge of the energy distribution of the nuclei participating in these reactions is important due to their exponential type of dependence on the collision energy. Two experimental techniques were designed and tested for recovering the energy distribution of liner protons incident on the CD₂ target by using optical detectors and ion collectors. It is shown that the combined use of these two techniques could provide relevant information on the energy distribution of the accelerated protons in the liner. The estimates of the upper limits for the astrophysical S factor and effective cross section of the pd reaction in the proton-deuteron collision energy range of 2.7–16.7 keV are obtained: $\bar S_{pd} (E_{pd} = 10.2 keV) \leqslant 2.5 \times 10^{ - 7} MeV b;\overline \sigma _{pd} (2.7 \leqslant E_{pd} \leqslant 16.7 keV) \leqslant 4 \times 10^{ - 33} cm^2 $ .     

Wide-aperture CO2 lasers pumped with an electron-beam-controlled discharge

This review paper presents the results obtained during the development and study of three high-power wide-aperture CO ₂ lasers (λ=10.6 μm) pumped with a discharge controlled by an electron beam. In developing these lasers, the method of formation of a space discharge at elevated pressures due to uniform ionization of the working mixture by an electron beam with an energy of some hundreds of kiloelectron-volts was used, which was proposed by researchers at the Instute of High-Current Electronics (IHCE). Institute of High-Current Electronics, Siberian Division of the Russian Academy of Sciences. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 5–11, April, 2000.     

Initiation of Explosive Electron Emission and Runaway of Electrons during Pulsed Breakdown of Dense Gases

JETP Letters - A mechanism for the initiation of explosive electron emission at the interface between the cathode and a dense gas is proposed. It is based on the accumulation of positive ions,...     

Compression of a Runaway Electron Flow in an Air Gap with a Nonuniform Magnetic Field

JETP Letters - The first results of study of the compression of a picosecond runaway electron flow in an air electrode gap by a pulsed guiding magnetic field increasing along the electron...     

Control of ellipsoidal trajectories: Theory and numerical results

An integral functional is optimized over set-valued trajectories in a differential motion control model under state constraints. The motion trajectories are assumed to be ellipsoid-valued. The construction relies on a suitable version of Hamiltonian formalism. A key point is that the solutions are described as matrix functions in terms of tensor analysis. The approach is especially efficient as applied to high-dimensional systems.