Laser-induced vacuum discharge as a source of hard X-ray radiation

The features of dynamics of fast laser-induced vacuum discharge with a rather small values of amplitude of current (≤ 10 kA), as well as the voltage and energy of the capacitor bank (≤20 k V and 20 J accordingly) are investigated depending on conditions of their initiation. Two various types beam-plasma instability are revealed. It is found that the first of them are realized at the initial stage of the discharge and is caused by a pinch structure presence in front of a cathode jet extending in vacuum. The second one arises at the top or recession of the current and is accompanied by the generation hard (the energy ≤100 ke V) Bremsstrahlung radiation from the anode area. Excess of the energy hard components of radiation over the potential of the current source is associated with the effects plasma - erosive disconnection.