PolHe3 Target Coil Rotation Plan, Mar 2020

Target coil rotation planned for March 13--20

Nominal 1-week downtime in Hall C to rotate target coils, install new cell, and transition to d2n program

Friday, March 13
- It would be useful for Ethan, Bert, and the Techs to get in in the morning (after panels are off) and talk through the job
- Techs load up hardware for Hall in ESB in the morning
  - Locate the extra beamline windows
  - Optics table for Compass measurements
  - Field measurement jig?
  - Parasitic Cerenkov test hardware/stand
- Beam off at 8am
- Radcon Survey -- Move to Controlled Access
  - Prep to open the Enclosure
  - Laser controlled access
- Final measurements on target cell (EPR, etc)
- Plan for Hall to move to Restricted around 1pm
- Work through remaining DAY, SWING
  - Bleed up beamlines *with N2* to allow up/downstream stubs to be removed (Gaskell, Marble)
  - Put guards on the up/downstream window spools
  - Put guards on HMS/SHMS windows
    - NOTE: Be beamline windows need to be protected from air (put in Rad bag and fill with dry nitrogen?)
    - NOTE: Removal may be deferred to Saturday (in which case the Hall C Techs must be able to remove both the up- and down-stream windows)
  - Target Group work (with RadCon support -- RW-II environment!)
    - Remove the target enclosure panels (minimum 2; perhaps all?)
    - Remove target ladder/cell
    - Remove reference cell
    - RadCon will remove their Contamination mitigation sheet under the target ladder

Saturday, March 14
- Remove Be beamline window spools (if not done already)
  - Upstream beamline must be bled up with nitrogen at this point
  - NOTE: Be beamline windows need to be protected from air (put in Rad bag and fill with dry nitrogen?)
- Techs w/ Target group rotate the coils
  1. sharpie mark corrector coil location and rotations (so they go back in the same way)
  2. remove 4 corrector coil stands let corrector coils rest on bottom
  3. tape measure locate 4 new 3/8-16 tapped holes for the corrector coil stands (drawing linked below)
  4. check for items that will affect coil rotation
  5. rotate helmholtz coils ccw 45 degrees (to zero)

Sunday, March 15
- Complete rotation, recable where possible keeping in mind that we may need adjustments with Survey support on Monday
- Install the compass measurement optics table (remove ladder to upper target platform)?

Monday, March 16
- Survey and Alignment
  - Confirm target and beamline laser alignment
  - Support setup for Field and Compass measurements (start in Swing?)

Tuesday--Wednesday, March 17, 18
- Reinstall beamline window spools, pump down beamlines when ready (install protective window guards)
- Possible pointing Surveys for SHMS, HMS (TBD)
- Field and Compass measurement continue as needed
- Install reference cell, leak check, etc.
- Install target cell and ladder as soon as possible
  - Recommission target and start spinning up ASAP (through SWING and OWL as needed)

Oven bottom plate (Arun/Bert)
- Follow up with Vince Pope in Machine shop (Arun?)

Kepco power supply status (Bill/Todd?)
- Bill will update us on Wed
- We need to establish what target angles will be (remotely) accessible (90, 180, -90?, 0?)

Target cell Austin (Xiaochao?)
- Only 'Reduced set' of density measurements available now, will continue measurements this week (issues with laser at UVa?)
- Wall and window thicknesses done
- It would be best for it to arrive at JLab on March 10 (at the latest) to allow locals to mount cell in oven plate before they get involved with target work in Hall.

Lots of preplanning to be completed (RadCon, Techs, S&A, Target group, etc)
- Had job walkthrough meeting this (Monday) morning with the above parties -- so far, so good
- Must coordinate Tech support with the parasitic test installation plans

RW-II training for JP, Arun, Brad, Bill
- Test is taken, awaiting the practicum (RadCon)

Main page is here: Pol_He3_Field_Mapping_Data (Field and Compass data)