Emission of plasma escaping from a heterogeneous solid (granite) under an electric discharge near its surface

The electrical breakdown of air near a granite plate causes sequential release of several hundred plasma jets consisting of electrons, positively charged ions, and Si, O, and other atoms. The release duration of each jet does not exceed ～10 ns, and the interval between them varies from ～10 to ～300 μs. It is assumed that the shock wave increases the lattice strain in dislocation pile-ups to such values at which the ground and excited state levels begin to cross. This leads to transitions between electronic levels, breaking of interatomic bonds, and emission of positively charged ions and electrons.