Beam down for SASE1/3: SASE1 XTD2 vacuum issue
Vacuum interlock of the SA1 / XTD2 solid attenuator area triggered closing beamline gatevalves.
VAC-OCD is investigating. No beam possible for SA1/SA3 since 7h18.
The vacuum interlock trip is a real vacuum problem. It could be temporarily circumvented to re-establish beam operation in SA1/SA3, BUT IT IS NOT FIXED.
Beam re-established at 8h50.
Currently all attenuators arms are OUT. The vacuum pressure is still high, returned below critical, but any attenuator movement can increase the vacuum pressure from the leak.
Further assessment by VAC in the next hour(s) will decide if a tunnel intervention must happen today or can be delayed until after the weekend. |