Run Planning Meeting Notes, Feb 13-Feb 19, 2020
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Thursday, February 13
- Last 24 hours
- Accelerator down 8:00-noon, hall in controlled access
- Beni went into hall to work on CDC boards
- Radcon released failed goni motor from tagger hall, taken for repair
- start counter dark pulse measurements (raw mode random triggers)
- Lubomir adjusted FDC thresholds
- other activities during controlled access...
- Quick-check harp scan at 12:15pm
- Production started at 12:30pm
- 200M evts collected, 46 minutes ABU
- Solenoid trip at 2:30 -- detailed report from experts
- cause of trip -- over-temperature on PS component
- subsequently discovered -- controller communications issue
- solenoid will not ramp, shifts cancelled until 8:00 2/13
- Hall currently in restricted access
- acid flush of PS cooling loop underway, finished by noon
- after that, diagnosis and repair of PS controller
- if all goes well, should be able to start ramp by 5:00pm
- Accelerator down 8:00-noon, hall in controlled access
- Reports
Friday, February 14
- Last 24 hours
- 8:00-noon, hall in controlled access
- acid flush of solenoid PS cooling loop
- work on PS controls started around noon
- work-around found for electronics issue
- hall restored to beam permit at 15:00
- solenoid current ramp started at 14:30
- 0 - 800A, wait
- 800 - 1000A, wait
- 1000 - 1200A, wait
- 1200 - 1360A, wait
- 1360 - 1350A, then go!
- ramp completed around 22:30
- Production resumed at 22:30pm
- Meanwhile, attempt at high-intensity accidentals test
- all detector systems turned off except: PS/PSC, TPOL, TAGM
- JD70-106 radiator, 2.1 uA
- beam was very unstable, attempts to understand it
- no change in gain setting of active collimator was needed
- we think that BPMs were saturating at 2.1 uA, driving the locks awry
- accel turned off the locks at 250nA, then ramped up to 2.1uA
- no coherent edge was visible in TAGM at any of the 4 settings (0/90 and 45/135 PARA/PERP)
- spent considerable time doing nudges, no change in TAGM spectrum
- finally, decided just to take data at 2.1uA
- one run, maybe 5 minutes of 2.1uA beam over ~1 hour period
- alignment of JD70-106 is a mystery -- what were we doing wrong?
- 8:00-noon, hall in controlled access
- Reports
- PS / active target / main trigger instabilities -- Alexandre Deur
Monday, February 17
- Last 72 hours
- ...
- Reports
- Potential improvements from realignment of JD70-105 -- Richard Jones
- PS / active target / main trigger instabilities -- Alexandre Deur
- another dip in the collimator transmission fraction, amorphous run -- Justin Stevens
- systematics of PS/tagger ratio variations -- Richard Jones