On the density distribution of a plasma generated by a femtosecond laser prepulse

We consider the results of computational experiments concerning the expansion of a plasma generated by laser radiation at the stage of a nanosecond "prepulse" ahead of the main femtosecond-range pulse. A series of plasmodynamic calculations has been performed for various laser target materials. It is shown that, within the framework of the considered problem statement, which corresponds to typical conditions of full-scale experiments, the distribution of the laser plasma density as a whole is satisfactorily approximated by a simple three-parameter formula.