[BTeam] minutes 04/07/2020

[Yves Roblin]

We discussed mainly the strategy for restarting the machine. The current working assumption is that we would run for six weeks with up to two weeks of setup time ahead of it.

 The cryo group estimates that it will take about 2 weeks to transition from 4K back to 2K. We asked them to do the injector/NL cryomodules first in order to allow for the injector group to start first.

The tunnel/magnet warmup will take about 3 days. We will proceed like last time where the AC was turned off and the magnets turned on in order to get to equilibrium faster.


The consensus for the startup method is that we will load the optics we had when we shut down and check that it reproduced. We expect that the Halls will be ready since they  are already at 4K. If not, we can send three passes to the bsy dump for some of the tests.

Once we check that it reproduces, we will try three different ARC1 M56 optics (with tune beam to 3R) and measure the M56 and determine which one is closer to the truth. Once that is done, we will load this optic and rematch appropriately (inj->nl , arc1 spreader, arc1 recombiner)

Reza raised the point that one might see if the ambient conditions (vibrations,etc..) are quieter than usual and document that, particularly regarding the C100 behavior.

The followup from last week was that
  for the troubleshooting guide, Todd will send me a list of people that will work on it from CASA's perspective. I will ask OPS (Brian or Paul) to designate a person to work with them.
 regarding the beam loss document, I am still waiting for contributions. I will have my piece in before next tuesday (simulation of the measurements, implications on determination of bunchlength and intrinsic energy spread) . Mike  McCaughan has volunteered to write a part about the BLM system itself (how they work, etc..)





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