1. Run coordinator report March 23 – 30, 2011
Brad Sawatzky
JLab
Hall C Weekly Meeting
March 28, 2011

2. Summary (1) Fix bad vacuum in beamline downstream of target
Noted that there was a significant hot-spot at the 1 o'clock position (roughly 10x higher than 7 o'clock)
Extensive leak checking up and down the line
made difficult by the poor vacuum, RGA doesn't work well
found large leak at seal on downstream bellows flange, (partially) resealed when 3 bolts were tightened near the 1 o'clock position
Working hypothesis is that small-angle Mollers, etc. are being swept by QTor into the flange. Did a quick test plan on Thursday with tune beam and recently repaired dump viewer:
Primary beam is indeed steered up and to the right – ie. in the direction of the hot spot.

3. Beam Spot at dump w/ QTOR at 2.0 kAmp

4. Beam Spot at dump w/ QTOR at 8.9 kAmp
Roughly 2cm shift toward upper right.
Jay attempted to find a magnetically neutral trajectory. No Luck.
Best indications are that this shift has been there since summer. Can not find ELOG to verify one way or the other.

5. The Plan® Developed with input from Ops, JRRP, Radcon, ...
Replace the gasket at the leaky flange.
Add thermometry to flange.
Nominal warning limit is 125 C, “HIHI” is 175 C (stay above the “knee” in Al 6061-T6 tensile strength vs temperature)
Add cooling fan on bellows/flange region.
Pre-run piping for water cooling around bellows/flange, leave connection points well outside historical radiation area. Not connected now, but could be hooked up later if needed.
Updated the COO with section discussing regions that accumulate significant radiological activity.
Engineering will run some models to get a better feel for thermal stresses on joints in the bellows region.

6. To Do List Get back up and running! Un-park target.
Test plan for Scanner to study effects of MD pre-radiator.
Scanner has been repositioned downstream of MD in preparation.
Get back up to production running at full current
Do this in steps, while monitoring temps and watching for plateau.
Moller on Wednesday?
There was a spot move last Thursday, this will be first polarization measurement since then.
Miscellaneous
New hardware for cdaql3, moving bulk of online analysis load to that machine. (Paul says we're close on getting the full analysis stage moved to the Farm.)
FFT and position difference studies continue (Buddhini, Jay: care to comment?)
Fill shift schedule!

7. Shift Schedule is “sparse”