Fast Timing Drifts 

When we see timing drifts fast (~1ps/min), according to the time tool, it’s likely that the hxr rf stabilization script got killed, check the status in the Grafana, report it to # lcls-timing-ops slack channel and get Charlie (Chengcheng Xu) notified:

Timing_Phase Cavity_Cable Stabilizer Status

  • The first panel is the phase shifter doing the compensation
  • Monitor the RF drift on the second panel from the top
  • Charlie needs to restart the script to make it work again

Slow Timing Drifts 

Slow timing drifts are monitored by the time tool edge. If we see that the timing is drifting out of the ~2.5 ps window, we can bring it back with the lxt motor:

  1. lxt_ttc.mv(0)
  2. lxt.mvr(VALe-12) # move VAL ps, looking at the timetool edge move until it’s centered
  3. lxt.set_current_position(0) # re-zero lxt