The dynamics of the expansion of two colliding plasma plumes in ambient gas has been investigated via hydrodynamical simulations. Experimental observations of a single plume, generated by high-power pulsed laser ablation of a solid target in ambient gas with pressure of about 10-1 Torr, show possible Rayleigh-Taylor (RT) instability. Our numerical simulations with two plumes find RT instability in low pressure gas, in which single plume expansion cannot cause instability. In addition, the RT instability is developed for about 10ns, which is extremely fast in comparison with the necessity of a thousand nanoseconds in the case of a single plume. The theoretically derived density condition for stability, plumegas, is satisfied in all performed simulations.
Plasma astrophysics and laser experiments: hydrodynamical simulation of colliding plasmas
TUDISCO, SALVATORE;
2010-01-01
Abstract
The dynamics of the expansion of two colliding plasma plumes in ambient gas has been investigated via hydrodynamical simulations. Experimental observations of a single plume, generated by high-power pulsed laser ablation of a solid target in ambient gas with pressure of about 10-1 Torr, show possible Rayleigh-Taylor (RT) instability. Our numerical simulations with two plumes find RT instability in low pressure gas, in which single plume expansion cannot cause instability. In addition, the RT instability is developed for about 10ns, which is extremely fast in comparison with the necessity of a thousand nanoseconds in the case of a single plume. The theoretically derived density condition for stability, plumegas, is satisfied in all performed simulations.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
