[BTeam] summary of meeting on 02/11

[Yves Roblin]

1) radiation load on east side of machine

We discussed ways to address this. One consideration is whether or not we have longitudinal tails on the beam.
A couple of days ago, it was found to be the case on C and A beam. the 1A sync light monitor was used in tune mode and we adjusted
 gang phase of NL.  This monitor is now dead.

The plan would be to fix it (replace camera and maybe shield it better) friday during
the time that we are reverting the spin to the longitudinal configuration for Hall A.

After it is fixed, we can characterize the beam longitudinal profile at the exit of injector. That should allow us to determine the amount of
phase offset one should put in 0L04 to get the bunch upright. We have the tools to do these measurements.

We can correlate the bunch orientation with the amount of activity in the BLMS on the east side.

So the sequence would be :

  have Joe Grames take 30 minutes to check the system for being able to do the test on ion trapping
  then do the spin adjustment for the hall a running conditions
  in //, take an access to fix the 1A sync light
  when beam is back, do the bunch characterization on 1A
  send beam to Hall A at 150 on their carbon target, check BLM activity
  adjust 0L04 to make the bunch upright (using the data from the measurement)
  correlate with the BLM activity.


Please everybody who is involved, send me an ATLIS # . All of these should have an ATLIS.

2) orbit lock and ffb behavior after restoring from a trip.

Options after coming back from a trip:
 1)  ramp up immediatly, trust the position monitoring software and ion chambers to trip if we had a big offset
 2) ramp up to 5 muamps instead of two to see if injector orbit lock behaves better
 3) only enable injector orbit lock after we are ramped up
 4) develop software to look at orbit changes and compare the before to after the trip. if its within a window (to be determined) , reenable ramping to CW.

The first three options could be done easily. The last one requires a bit of software development.

I am not sure we came to consensus on what to do on this option.

Yves




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