1. Proposed Operating Guidelines for Opening
the MSE / BES Shutter
Steven Scott
C-Mod DNB Meeting
April 11, 2005

2. We need to protect the MSE optics
We have a large investment ($1-$2 million) in the MSE diagnostic.
The C-Mod physics program needs MSE q-profile measurements.
Disruptions coat the MSE optics.

3. Recommended Operating Guidelines
The MSE / BES shutter should not be opened if high-current (>0.9 MA) disruptions are expected.
This applies with shutter is opened for routine data acquisition and when shutter is positioned to use in-vessel linear polarizer.
Special care when Ip > 1.4 MA.
We should open shutter only when we expect to get useful plasma data or calibration data.
No ‘routine’, aka fishing-expedition operation.
We may relax these stringent criteria over time.
Essential that we resolve MSE calibration issues before putting MSE optics at risk.

4. Recommended Operating Guidelines, cont’d
MSE/BES & plasma status should be monitored continuously by an on-site diagnostic operator.
Read the mini-proposal before opening the shutter.
Know the expected plasma conditions for the next several shots.
Don’t leave the control room for more than ~2 consecutive shots (20 minutes).
Talk with the physics operator before opening the shutter.
Has the experimental program changed?
Will there be an opportunity to close the shutter if needed?
Make sure he understands that you should be informed if the experimental program changes direction – particularly with respect to disruptions.
Record time or shot number of shutter opening in logbook.
Close the shutter at the end of the day.
Make clear entry in the electronic logbook (topic=MSE).

5. Boronization, ECDC & Daily Startup
We should implement a double-check system before boronization
Written sign-off by
two member of the MSE / BES team, or
by one member of the MSE / BES team + a C-Mod technician who verifies the position of the push-pull.
Save the copy of the written sign-off.
What to do for ECDC?
Daily startup
Do we want to wait for one successful plasma shot before opening MSE shutter at start of each day?