Effect of Accumulations on Imaging Processing for Laser Plasma Dynamics

Laser plasma instabilities and shock waves are relevant to many endeavors, including laboratory astrophysics. Image accumulation will allow the study of such plasma phenomena in greater detail. A graphite target secured to a motion stage in a 20 mTorr vacuum was repeatedly ablated by Nd:YAG laser pulses (532 nm, 5 ns), creating an expanding plasma. An ICCD camera captured the expansions at 200 ns. The experiment was automated in MATLAB, allowing for hundreds of shots to be taken. As part of processing in MATLAB, images were added together and averaged with different numbers of accumulations. This resulted in increased detail with greater number of accumulations, although there were no significant improvements beyond 100 accumulations. The use of accumulation techniques was successful in this experiment, giving us a helpful tool for future plasma diagnostics efforts.