Laser-Induced Non-Equilibrium Plasma Decay in a High-Speed Flow

For development of applications based on the short-pulse laser energy deposition and laser induces plasmas, especially for laser diagnostics in high-speed flows understanding of plasma properties is crucial. In this study we used a detailed multi-species drift-diffusion model to simulate dynamical behavior of the femtosecond laser filament in a free stream flow at Mach number M=5. The laser plasma model is used to characterize the decay of electrons, ions, and electronically excited species in space and time. Spatially resolved profiles of the triplet electronically excited state of nitrogen follow experimentally observed fluorescence intensity distribution from measurements of the velocity field using femtosecond laser electronic excitation and tagging.