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• The accelerator provides exactly 910,000 buckets in exactly 0.98 seconds
• The accelerator patterns repeat on this 0.98s interval
• The ratio of these two numbers is what gives rise to the 929kHz (~1MHz) machine rate.  Equivalently: accelerator rate is 13/14MHz, bucket period is 14/13us.
• timing eventcodes arrive ~100us prior to beam
• The 71428Hz rate is special: common between LCLS1 and LCLS2

Presentation

A presentation from Matt:

https://docs.google.com/presentation/d/1QumkWlhA9Q8PW40hlyMkr0HZwBB4UBOK/edit?usp=sharing&ouid=118434024476101633307&rtpof=true&sd=true

Recording of Matt's presentation on the timing system.

Link to Matt's presentation.

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