Date

Attendees

Discussion items

  • Lisa and Sonya had another test of Auto Setup rework (more controls in IOCs instead of HLA).  Full machine took ~5 minutes.  Really great!
    • Didn’t include the SSAs
    • Need SSA write permissions, which is a large infrastructure change that will take time
    • Not reasonable to squeeze in before the start of the Winter Downtime
    • Andy points out - look out for long delays for the HE SSAs.  1 minute delay from DC enable to RF enable
  • Plan for shutoff:
    • Will detune CM02-35 to cold landing on Sunday afternoon
    • Will do field emission characterization + cold landing for CM01 really early Monday morning
  • When to do SSA run up, etc.
    • SC machine needs POMMs for 2-3 hours, like NC
    • Should make a list of SSAs for troubleshooting
  • Have seen some drifting phases lately
    • CM12-3 and -4, CMH1-7 and -8
    • Andy thinks it’s likely the LO that has problems
  • Andy thinks that the SSA characterization needs to be dramatically enhanced
    • Wants SSA internal numbers + forward/reverse numbers
    • Thinks this would help diagnose/solve a lot of problems
    • Automate SSA drive level max
    • Get rid of lower bound failure
  • Lauren suggested a post-mortem for the helium oscillation that looked like PRL noise
    • Would be an interesting case study to share during the downtime
  • Janice says ops are thinking about how to better communicate cavity instabilities causing beam instabilities, how to track down cavity instabilities, etc.
    • Should show up as AOTs, but ops aren’t seeing that
    • Check the hierarchy there
    • POTs can be both be reactive and mask other problems on the cavity display
    • Sebastian suggests looking at the amplitudes
    • PRL, PJT, and FBS are higher than AOT and POT
    • PFB is below AOT and POT
    • Make a display with the “four resistor boxes” alone?
    • Look at the rate of change of the fault counters?
  • Other downtime prep
    • STCAV0 installation will need valves closed
    • Turn off water-cooled magnets (make sure it’s on the downtime script)
    • LO tightening work will need followup calibration
    • Turn off all the superconducting magnets before 4K, but after we care about dark current
    • Close vacuum valves in non-particle free areas
    • Check work in particle-free area to see if we need valves closed
  • Cavities that keep getting turned off for UH/DH: CM27-2, CM33-2, CM34-2?
    • Turn down gradients?
    • Try active resonance control?
  • Make time to study active resonance control
    • Jorge is very interested in this
    • Try on CM07-2, CM19-1 and -2 first
  • SC recovery scheduled for January 16th, after the weekend after STCAV0 installation is scheduled to finish

Action items