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The interaction of nanosecond pulse laser induces thermal processes which results in the localized melting and vaporization of material and therefore generates micro plasma at the surface of the solid.At the same time laser radiation interacts with the expanding plasma and high charge states are produced due to ion-electron collisions,inverse bremstrahlung absorption and multiphoton ionization processes.After production,the plasma expands at supersonic velocity and self generated electric field in the plume determines the energy and flow of the ions in vacuum.This non-isotropic electric field is directed mainly along the surface normal,and its duration is of the order of the laser pulse width [1].