To track the time jitter between X-ray and optical lasers on a shot-to-shot basis, a real-time diagnosis using the femtosecond X-ray/optical cross-correlation process technique is referred to as the time tool. The ionization of x-ray on the YAG crystal turns opaque to the optical light allowing locating t0 timing. The . In figure 1, the shadow area represents that the x-ray arriving arrives earlier than the laser pulse. The Therefore, the dashed line represents the t0 position. Issues: The old time-tool setup using the leak from the drive beam , had only 5Hz , varied intensity, pulse duration by changing drive conditionà poor signal to noise ratio. rep-rate. The intensity and pulse duration were varied with drive beam.
The time tool is cross-referenced to the target plane using another YAG window at the target center position, with a small aperture temporarily inserted in the drive beam to spread the laser focus at the target plane. The time tool measures an RMS jitter of ~ 100 fs between the MEC laser and the x-ray beam.
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