A. M. Boichenko

CuBr-Ne-HBr laser with a high repetition frequency of the lasing pulses at a reduced energy deposition in the discharge

Experimental and computer studies of the CuBr laser with periodic-pulse pumping are performed with and without addition of HBr. The analysis based on the numerical simulation reveals how additions improve the lasing characteristics of this laser at both typical (10 to 20 kHz) and higher (up to 100 kHz) excitation pulse repetition frequencies during the operation with a low energy deposition in the discharge. This allows the lasing pulse repetition frequency to be increased in the experiment to 750 kHz, which does not seem to be a limit as yet.

Pumping of lasers and lamps by discharges based on the background-electron multiplication waves

Experimental realization of a new discharge type, i.e., the discharge representing a background-electron multiplication wave, is considered. Experimental and theoretical data illustrating the applicability of this discharge type to excitation of laser and lamp radiation sources are presented.

On the influence of the voltage pulse rise time and cathode geometry on the generation of a supershort avalanche electron beam

The influence of the voltage pulse rise time on the amplitude of a runaway electron beam and X-ray generation in air and nitrogen under atmospheric pressure is studied experimentally and theoretically. Generalization of the whistle criterion for the case of a nonuniform field is suggested. It is shown that the maximal energy of beam electrons and the beam current amplitude grow when the voltage pulse rise time decreases. It is found that the amplitude of the runaway electron current reaches a maximum at a certain curvature of the cathode. The maximal energy of electrons increases when the radius of curvature of the cathode exceeds the value at which the beam current amplitude is the highest. If the field is nonuniform, its critical value at which many electrons run away is more than an order of magnitude lower than in the uniform field.

Simulation of a CuBr Laser

A method to calculate the prepulse concentrations of the CuBr molecules in the active medium of a CuBr laser is proposed. A comparison with the available experimental data is presented.

Barrier-discharge excilamp on a mixture of krypton and molecular bromine and chlorine

Spectral and energy characteristics of a barrier-discharge excilamp on a mixture of krypton with bromine and chlorine molecules that emits in the range 200–300 nm are presented. The radiation spectrum contains the bands of the B → X transitions of the KrCl* (222 nm) and KrBr* (207 nm) molecules and the band of the D′ → A′ transition of the Br*2 molecule (291 nm). It is demonstrated that the bromine content must be higher than the chlorine content in the triple (Kr−Cl2−Br2) mixtures that are optimal with respect to the radiant power. A radiant power of 0.7 W and an efficiency of 3% are realized. A multiband barrier-discharge excilamp based on the triple mixture exhibits a potentially long lifetime.

The nature of emitting microdischarges in barrier-discharge lamps

The nature of the microdischarges of the barrier discharge is studied. The distribution of the fields generated in the discharge gap by charges on the dielectric surface is determined, the microdischarge parameters are estimated, and the results obtained are compared with the experimental data.

Breakdown of gas gaps in a nonuniform electric field at a subnanosecond voltage pulse rise time

The influence of the nitrogen pressure on the breakdown voltage in a nonuniform electric field is studied. Voltage pulses with nanosecond and subnanosecond rise times are applied to the gas gap. Simultaneously with the application of voltage pulses, supershort avalanche electron beam pulses are observed behind a foil anode. It is found that, when a runaway electron beam is generated and voltage pulses have a subnano-second rise time, the breakdown voltage rises as the nitrogen pressure decreases from 9 × 104 to 1 × 102 Pa. Experimental data are in good agreement with pulsed breakdown analytical curves.

Excess electron energy in vacuum diodes

The mechanism for generation of electrons with the anomalous energy in the spectrum of powerful nanosecond electron beams is investigated. One-dimensional propagation of the beam between spherical electrodes in vacuum diodes with a large potential difference is considered. It is shown that the excess electron energy increases as the curvature radius of the cathode decreases and the beam current is conserved. Theoretical results are compared with the experimental data.

Penning neon laser with excitation by background-electron multiplication wave

The Penning neon laser was studied in a Ne-H2 mixture excited by a transverse discharge. Theoretical modeling allowed the conclusion that the laser active medium was excited due to the background-electron multiplication wave passed through the discharge gap.

Spectral characteristics of a high-current pulsed discharge in xenon

The radiation characteristics of a pulsed discharge xenon lamp are experimentally and theoretically studied. The data on radiation spectra are obtained for various compositions and pressures of working medium, energies and time profiles of excitation pulse, discharge gap configurations, etc. Electron temperature and mean spectroscopic symbol of emitting ions are estimated. It is demonstrated that cw radiation (continuum) results from the photorecombination transitions.