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User name D. Parno
Log entry time 23:26:55 on December10,2008
Entry number 252909
This entry is a followup to: 252898
keyword=No Compton events for ~100 minUnbeknownst to us, MCC moved the beam position in the Compton chicane to try to address the problem of high rates. Unfortunately this moved the electron beam out of the interaction region, so there were no Compton events during this time. You can tell because there is no difference in the blue line (Compton rates) between cavity on/off states (the red square wave).
Fig. 1 is the zoomed out strip chart showing the situation before this adjustment and after the correction. Fig. 2 is zoomed in on the most recent time period so you can see the lack of Compton events more clearly. The beam position is coming back to the correct spot and we find Compton events again.
FIGURE 1
FIGURE 2
