9:47 AM: After struggling with the electrometer #29 for a bit, we managed to acquire a window only profile using version 1.5 of software. The results show noisy peak at 2% level, as previously shown. A careful inspection of monitoring data however, revealed an up to 10% bump at the center. Another inspection of scanning chamber reading versus position showed a noisy top up to 10%, but correlation between the two chambers seemed to cancel this effect, giving a noisy level at the peak region of only 2%.
10:22AM update: The cause is feebback effect of Joakin chamber. Since the beam is blocked by the A16 chamber, the Joakin chamber show lower reading, which cause Vickers to increase beam current. Now the noise is better.
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