Analysis of spectra of acoustic signals generated by high-power pulsed laser radiation propagating in the atmosphere

摘要

Results of experimental investigations of the spectra of acoustic signals generated by high-power pulsed laser radiation propagating through the atmosphere in the breakdown mode are presented. Laboratory experiments on the study of the spectra of acoustic signals generated by individual plasma formations were carried out using a GOS-1001 laser (λ = 1.06 μm, E_(max) = 1 kJ, and τ_L = 1 ms). Field experiments on the study of the spectra of acoustic signals generated by laser sparks were carried out using high-power pulsed CO_2 lasers (λ = 10.6 μm). The spark was made by laser beam focusing into the atmosphere at distances from 50 to 500 m. The density of acting laser radiation in the caustic region was varied from 8 to 20 J/cm~2. The special features of laser-induced spectra of acoustic signals radiated by individual plasma formations and discrete laser sparks are discussed.