Industrial quality applications of high-power lasers working at high repetition rates, including laserdriven particle acceleration, will require laser systems capable of operating in a stable and prolonged manner. Several factors can affect this stability, including the environment conditions, such as temperature or humidity, and the progressive heating of the optical components involved. Here we report on the evolution of the main laser parameters for a 45TW system operating at 10 Hz, showing that a significant change in the wavefront and direction of propagation, even when the laser energy remains sufficiently constant. These results highlight the importance for future laser systems to integrate closed-loop beam tracking diagnostics that can correct the temporal evolution.

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