Log entry time 23:32:29 on April 18, 2004

Entry number 82513

Run Coordinator's Report for 17 April Swing to 18 April Swing

Summary

Continued with production data taking on LH2 data during owl shift. Angela took her deadtime studies data at 3 currents: I=10,20, and 30 uA. Returned to production data taking. Frequent beam trips and IOC crashes towards the end of day and beginning of swing shift. MCC fixed a problem with beam steering which hopefully will improve stability.

Significant News

• Production data taking with parity quality beam on LH2. Very smooth running during owl shift.
• Three 1hr long runs taken for deadtime studies at I=10, 20, amd 30 uA. Analysis underway.
• IOC SE20 crashes continue on a rather regular basis (still about 2-3 per shift).
  Paul King's new alarm script is catching the crashes, the runs were stopped immediately and the IOC rebooted.
  The script runs on jeffylab in an independent window. See Paul's log-entry number 82375 for details. The system has a sort of "hiccup" (a single alarm) when beam comes back after a trip, but seems to work well otherwise (continuous alarm when the IOC gets stuck). In addition there is also a new script by Steve Williamson that gives a sound-byte when beam goes away and returns (very useful to notice beam trips). See Steve's log-entry number 82492 for details.
• MCC had trouble delivering stable beam. They discovered a steering problem, which was corrected (ELOG-entry 1207536). Hopefully this will improve stability during the night.

Short term Plans

• Continue with LH2 production running until Monday morning 07:00am.
• Shutdown for CD-0 tour. Here is the current schedule:
  • 07:00 Beam OFF. Target out of beam. Ramp G0-magnet down.
  • 08:00 Sweep of the Hall
  • 10:00 - 11:00 Tour of the accelerator and the Hall
  • 11:00 Lock up and sweep of Hall(s) and machine
  • 12:00 Beam restoration
  • 13:00 Restore Physics program
  • There are some differing statements about whether the tour will be visiting the Hall C counting room. The latest statement says that the tour will NOT be coming into the counting rooms. Stay tuned .....
    Please limit time in the Hall to absolute minimum. No work should be done during the time of the tour.
• Green block measurement during Monday's tour. This was proposed by Louis. Since we do not need target or magnet for this, but only HV and DAQ this may be something useful we could do during the time.
• IOC SE20 replacement during the Monday shutdown (??).
• Moller/IHWP insertion/Moller after beam restoration from the CD-0 tour on Monday, while we ramp G0-magnet back up.
• Beam energy measurement next week during the day shift. Mark Jones will be present for this.
• Continue with LH2 production running.

Longer term Plans

• Moller/IHWP insertion/Moller every three days.
• A long (restricted) access is planned for next week to pump the cryo line for the magnet (Damon). Contacted PD to rearrange the beam studies schedule in order to get a 4 hr long Beam studies periond one day next week during which we can access the hall. This way we won't lose any beam time for production running. Date of access will be probably be either Wednesday or Thursday. During this shutdown we may also move the IOC SE20 to a more shielded area. This depends however on how the latest replacement (which will possibly be installed on Monday) will work.
• Beam energy measurement of the beam into Hall C (Mark Jones).
• PMT gain calibration at 1uA (6hrs at Julie's request)

Concerns

• Even after replacing the IOC SE20 controller board there are still rather frequent IOC SE20 crashes. The IOC crashes in way that makes it hard to detect: The EPICS values freeze at a non-zero value. If this happens the IOC has to be rebooted. Paul King has written a script that gives an audible alarm if the G0 BPM flatline and the PD will talk to the software people to get an alarm implemented at the MCC. We will also try to find out if the IOC can be moved to a more radiation safe area in the Hall during the long access next week.
  When the IOC crashes the run should be immediately stopped and a note put in the end-of-run comments and in the run summary that states that the IOC crashed at the end of the run.
• Temperature in the electronics cage is rising during the afternoon hours above alarm levels. We started the big fan in the cage to increase airflow to the FR electronics rack. Steve Williamson will post a plot in his shift summary.
• Spikes in French electronics, possibly caused by a network problem. Paul King claims that the buffer of ROC3 may not be big enough (currently ~2sec) and could be increased up to ~3sec, but then we would have to boot ROC3 every time we change the configuration. Shift crew should also clearly mark runs with spikes.
• NA LTD errors still occurring at a small rate. Brian has generated a "HowTo" document for trouble shooting.