THOMAS JEFFERSON NATIONAL ACCELERATOR FACILITY
ACCELERATOR OPERATIONS CREW CHIEF SIGN IN FORM
Date : 02-07-23
Time : 07:39:02
Day : Tuesday
Shift : Day
Crew Chief : Carlino
Program Deputy: Letta
Team : X
Arm : RADCON
Designated SSO: Schoene
Operators : Schaumloffel, Schoene
This stamp certifies that the above Crew Chief has read/reviewed/received the following:
The following cavities have been GSET 0:
RF Status: Bad
Tuner Status: Good
Comment: GSET 0 - stepped off +100k - PMES all over the place, had issues during RF recovery
current to Hall A is slowly draining off as I try to tune their optics - then there's a discharge in the injector, positions are thrown into disarray, and the beam profile changes. It's becoming almost impossible to tell which profile changes are due to my quad adjustments and which are due to fluctuations elsewhere in the machine.
Fig 1: positions are all over the place, current drains off while sending tune beam.
Fig 2: post-discharge excursion in y position. -0.10 is nominal.
Fig 3: beam sizes for consecutive harp scans with no quad changes.
It is interesting that the BLA loss signal, blue in middle pane, grew overnight with fixed currents A at 5 uA and C at 40 uA. I don't know what this means. It remains reasonable symmetric. No loss evident on NDX detectors, top and bottom panes. Ten BLA trips on owl shift, figure 2.