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Hi All,
We will have a beam line meeting at 10am Monday morning in the Group C conference room.
Agenda:
A) Hall B work - update: Stepan
Hello Takashi, I commented on the documentation in my previous email to the group responsible for the documentation at the wiki. One of comments was on the beam recovery is the moving SVT. Sorry, I should have looked at that more carefully before. So, what is the plan, are we going move SVT up and down every time we have beam trip? As we discussed before, we will have ~10 trips per hour. If we spent 2-3 minutes to recover (just ourselves) we never will see beam on the target. As I propose before, if SVT is not comfortable to run a close proximity to the beam, we should run at saver location, e.g. edge of L1 at 1.5 mm from the beam so that collimator will block it all. I think we should discuss this some more.Another point on the recovery, we probably want to turn orbit locks OFF before bringing beam current to ~few nA when nA BPMs gets stable and the initiate orbit locks. Otherwise there is a danger that non-reliable readings from BPMs can push correctors to steer the beam to wrong places. Stepan
Hi Takashi,I guess I am not understanding the meaning of this document. It looks the way you describe it is not a general procedure for beam recovery, but it is a mixture of procedure for recovery and to test/check the safe condition for SVT. May be we can get appropriatename and title for the document. OurMCC operators do read documents on run pages and this as it is will confuse them exactly what we are doing as beam recovery.
Ken and Takashi, The biggest problem I have with this document is the very last bullet. If this is a document to be used by shift people and MCC operators to restore beam after the trip (even only for initial stage of running), many times per hour, it should be confined only to the restoration of the beam, not moving the SVT. The way it is presented here it looks like you want to move SVT every time after the beam trip. May be we should clarify this at the next beamline meeting. Stepan