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“Electrostatic Shocks” and field-aligned currents are associated with discrete auroral arcs and low-altitude particle acceleration. We show that accounting for the two new elements with respect to the previous “static” and “Alfven wave” models, namely the transverse wave-guide for shear Alfven waves and plasma density dip in the center of the structure, is necessary in order to explain the basic features of this phenomenon. The characteristics dimensions of the structure correspond to the “stirring scales” of the auroral turbulence.

This report describes common features of natural (‘Enhanced’) aurora and ‘artificial aurora’ (AA) created by electron beams injected from sounding rockets. These features cannot be explained solely by col‐lisional degradation of energetic electrons, thereby pointing to collisionless plasma effects. The fundamental role in electron beam‐ionosphere interactions belongs to Langmuir turbulence. Its development in the (weakly‐ionized) ionosphere is significantly affected by electron‐neutral collisions, so that the heating and acceleration of plasma electrons proceed more efficiently than in collisionless plasmas. As a result, a narrow layer of enhanced auroral glow/ionization is formed above the standard collisional peak.

A description is given of a new class of transducers (sensors) of physical field parameters in which low-loss fiber waveguides are employed. It is shown that a high sensitivity of fiber-optic transducers can be achieved for various experimental geometries. Descriptions are given of the construction of fiber-optic transducers of elastic vibrations, pressure, temperature, electromagnetic fields, and ionizing radiations. A classification is proposed for fiber-optic transducers on the basis of the physical fields detected by them, in accordance with the effect of such fields on light traveling in a fiber waveguide, and in accordance with the interaction resulting in stimulated emission from fiber waveguides.

A load-bearing optical cable characterized by low optical losses was developed. A study was made of the influence of hydrostatic pressure and temperature on the optical losses in the fibers enclosed in cables of different configurations. A prototype of a load-bearing optical cable was made and the losses in this cable were 2 dB/km higher than in the component fibers.