Single-shot spatiotemporal plasma density measurements with a chirped probe pulse

High-power (>TW), short-pulse (<ps) lasers are generating significant interest worldwide due to their ability to generate secondary sources such as electrons, protons, neutrons, and x-rays, which have numerous applications that span nuclear physics, fusion energy, medicine, and industry. However, these high-energy, high-intensity systems experience substantial fluctuations in on-shot laser performance due to pointing changes and shot-to-shot variations in the amplification process. Measurements that scan a variable over multiple laser shots cannot distinguish between changes due to the scanned variable and changes due to laser system fluctuations, including changes in the target quality, laser pointing, and nonlinear effects such as filamentation. High energy laser systems also typically have lower repetition rates due to damage thresholds and thermal relaxation times, making multi-shot diagnostics impractical. This work reports the demonstration and first use of a single-shot, all-optical electron density diagnostic, which obtains 2-D electron density profiles vs. time for each shot, to measure the on-shot spatial and temporal formation dynamics of a plasma column produced at the Jupiter Laser Facility in Livermore, CA.