Formation of extended conducting channels in atmosphere

Some mechanisms of the formation of an extended (~1 km) conducting channel in atmosphere using the laser engine technology (Impul'sar program) are considered. The electric conductivity of a channel formed by electric explosion of a 90-μm copper wire up to ~1.6 m long (in electric breakdown) at a voltage not higher than 10 kV is studied. The requirements to the products of laser engine exhaust to atmosphere for producing a conducting channel, containing dispersion and condensation aerosols of hot particles of copper oxides (CuO, Cu₂O) and copper with an oxidised surface (from 50 nm to 300 μm in diameter), are formulated. Possible mechanisms of electric breakdown at the field strength E ≥ 52 V cm^-1 in the discharge gap are discussed. The electric conductivity of the channel formed by the laser plasma upon focusing the solid-state laser radiation on targets made of different materials has also been studied.