RC Meeting and Run Plan, Monday, January 13th 2020
RC Meeting Information
RC Daily Meetings are at 4:15 PM, 2nd floor Counting House Meeting Room
- Bluejeans remote connection information:
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- During the previous pumping (before closing up the target enclosure) we observed plateauing of the polarization due to masing effects for the transverse direction. For the longitudinal direction (which had a higher gradient than nominal), we observed similar behavior but with huge AFP losses. This was a common situation encountered by Transversity experiment folks and was addressed in the past by tweaking the magnetic field gradient.
- Long story short, during the most recent pumping, the longitudinal polarization looked very good (>50+% polarization) but take this number with a grain of salt. Overall, there is some tweaking to do to possibly get higher He3 polarization but nevertheless, we decided to close up the target enclosure and prepare for beam.
- We are currently taking 1-pass calibration data. We finished density measurements and optics runs. We will continue with our longitudinal and transverse asymmetry measurements for the rest of the swing + owl shift, provided the beam permits us. After that, we will move on to 5-pass tomorrow evening (?).
- Update the TO manual and have a walkthrough of the polarimetry software for all the target experts.
- Announce a TO class for sometime this week.
Current Run Plan
- Monday: 1-pass data with longitudinal and transverse asymmetries (https://hallcweb.jlab.org/wiki/index.php/1-pass_calibration_for_A1n_(Jan_2020) ). Are we starting off with Transverse or Longitudinal?
- Tuesday: Finish 1-pass at 8:00 AM, open the target enclosure, remove collimators, do a local EPR and close the panels. Transition to 5-pass.
- Wednesday: 5-pass beam and Moller measurement
- Thursday: TO class?
Notices in Effect for Shift Crew
- Policy for CANS-related hall status change: Make a logbook entry when the hall goes in, or comes out of laser-controlled access.
- Magnet policies
- HMS Q1 must be ramped down in 50A steps in all cases
- Do not ramp HMS Q2 to zero, only go to 10A and then switch off power.
- Inform the RC of any access that the Target Team requires. The RC will coordinate with RadCon to make everything run smoothly.
- The operators have been somewhat careful with our beam orbit locks. Please make sure that the orbit locks are enabled and the beam does not drift from its nominal position.
- Ramp rate lock instructions are here and added to checklist
- Temporary Laser instructions can be found here 
Ongoing Work in the Hall
Planned Accelerator Configuration Changes
- Keep target expert schedule filled out on whiteboard