[Halld] Commissioning update + shutdown plan

[David Lawrence]

Dear GlueX Collaborators and Friends,

 We are now less than 24 hours away from the end of our first beam commissioning period.
The beam is scheduled to be taken away on Sunday Dec. 21 at 8am. Please see instructions
below regarding post beam activities. Here are some highlights from the past couple of days.

- Friday early morning (~5am) there was another Solenoid trip. Appears to be the same problem
  with transient signal from Cryo (though no record of it on their end).

- A rogue script was accidentally let loose in our counting house that deleted a lot of directories,
  causing many issues with the online systems. No data was lost, but some time was in tracking
  down and fixing it

- After the chaos subsided Friday morning, it was noticed that our detectors were not indicating
  beam events. This was eventually tracked down by Paul E. to the Tagger magnet. It was apparently
  not cycled properly after the down time on Tues/Wed. 

- DAQ development has proceeded with a focus on increasing the event rate via multi-block 
  readout and increasing the TS buffer. We have seen event rates reported as high as 42kHz.
  We will finish running with our previous DAQ configuration though since we have not been
  able to confirm the data integrity with the block mode.

- We are receiving good beam now and will continue taking data with our loose fcal_bcal trigger
  for the remaining hours (minus any time used for additional DAQ or Trigger development.)


IMPORTANT: PLAN FOR SHUTDOWN
——————————————————

- Beam is scheduled to go away at 8am on Sun. Dec. 21. Shifts are cancelled starting Sunday at 8am.

- Hall-D and the Tagger Hall will be put into Controlled Access at that time but will not be
  put into Restricted Access until Monday Morning.

- When beam goes away Sunday morning, the solenoid will be ramped down. 

-  DETECTOR GROUPS ARE RESPONSIBLE FOR SECURING THEIR SYSTEMS FOR THE
   DOWNTIME PRIOR TO C.O.B. on TUESDAY DEC. 23rd! This may mean turning off HV/LV,
   chillers, etc. Please keep in mind that the halls will be in Controlled Access until Monday morning.

- Do not remove anything that has been in the hall during beam operations unless it has been 
  surveyed by Rad-Con.

If you have any questions, please call the RC phone (757-383-5542)

Regards,
David Lawrence, Acting  Hall-D Run Coordinator