Population inversion and gain distribution in supersonic mixed flow systems

Experimental results are reported for small signal gain distribution across a cavity of a mixed flow gasdynamic laser system at different turbulent supersonic mixing regimes. It is shown that the temperature range of the GDL generation regime can be extended up to 7000°K, and gain coefficients as high as 3.5 m⁻¹ be attained in a “double-freeze” supersonic gas flow. Basic advantages are discussed as well as the opportunity to obtain higher efficiencies in thermally pumped laser systems.     

Compact high-voltage accelerators of charged particles in space experiments

Some general problems of design and application of compact devices for the generation of pulse electric fields at a megavolt range in space experiments are discussed. The prospect of various applications of powerful electron beams for active diagnostics of upper layers of atmosphere, radiation belts and the earth's magnetic field is also reviewed. The proposed development of powerful impulsive devices is dictated by limitations of energy resources in spacecraft together with a need to get a good signal-to-noise ratio for reliable data recording. Compact devices which directly transform electric energy of a low-voltage source (solar batteries, chemical elements, nuclear reactor, etc.), into the energy of a megavolt charge particle beam of high impulsive power appear as reliable means for satisfying these requirements. In this paper, the basic practical schemes of energy transformation procedures are considered and the optimal operation parameters of high-voltage storage and transformer systems are discussed. Proper application of combined high-voltage insulation techniques result in the development of experimental models of heavy-current electron beam accelerators capable of generating beams of 300–500 kV, 3–5 kA, with a pulse duration of 15 × 10⁻⁹ sec at a frequency of 10 Hz. Typical applications of electron beam accelerators including the generator of electron-beam-controlled discharge laser beams are also described.