[Halld] Weekend Update

[Alexander Austregesilo]

Dear Collaborators,

A power supply for an accelerator RF module went down yesterday 
afternoon. It was brought up after only about 3 hours down time, but the 
same system failed again today around noon. This time, repairs were more 
invasive in order to prevent this failure mode happening again. As a 
result, we were down more than 6h this afternoon. Unless something else 
goes wrong, beam should be back soon.

Apart from this, we are progressing quite well with our low-energy 
program. We have recorded 3 out of the 5 requested full cycles of 
diamond+amorphous running, and the 4th one is more than halfway done as 
well.

On Monday, a possible leak in the east arc will be investigated during 
the system recovery period. Due to the time it takes to change machine 
state and sweep the linacs, we won't have beam for about 6 hours 
starting at 07:30am. The length of the down time is only an estimate, as 
it depends on what they will find down there.

The Beam Studies period is scheduled for Tuesday (8h starting at 
08.30am), where they will explore high current running (900kW). For this 
purpose, the halls A, B and C have to stay locked. As the beam will be 
unstable during this time, we decided to open up our hall to install the 
new beam pipe for the PrimEx experiment.

Best regards,

Alex Austregesilo
Hall D Run Coordinator