Confluence will be unusable 23-July-2024 at 06:00 due to a Crowd upgrade.
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A great and detailed explanation can be found here: LCLS 1 Event Generator for Dummies
In summary, the main LCLS-I timing is based on a 360 Hz frequency, which is divided in 6 time slots (TS), each running at 60 Hz, but with a different phase. The 120 Hz beam is a combination of slots TS1 and TS4, while the other ones are "empty".
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