[Bteam] No meeting today

[Arne Freyberger]

  NO BTEAM MEETING TODAY


    1 2009-09-23 Wed 14:00 No meeting

There will not be a B-Team meeting today.

    * Brief status Report
      Machine is running well since last Wednesday transport clean up.
      It is unclear if the Compton rate reduction was due to shifting
      the doglegs "out of the mud" and fixing the separator, or the
      thorough cleaning up of separation and transport lines by MikeS
      and Yan. The reason we are confused is due to the fact that the
      Compton detector was in a non-standard configuration all day
      Wednesday. Nevertheless the machine is in a "good place" due to
      all these efforts.

      The Beam Loss Accounting system is still has a large amount of
      noise, but the transport appears to be clean if one looks at the
      Beam Loss Monitors, Beam Scraping monitors, Hall-B harp scans,
      Hall-A compton rates. Yesterday the 500KeV kicker sensor was
      jumpered out to remove a 80Hz intensity fluctuations in order to
      minimize the issues with BLA system. With the this sensor jumpered
      out the 80 Hz noise was removed, but the BLA still fluctuates
      between 0 and 1.7 ? A of loss.

      The main issue this week have been establishing robust FFB
      configuration to both A and C. Sometime Monday morning, things
      drifted such that disabling/enabling FFB in the A line caused ep
      ion chamber trips. By carefully calibrating the FFB response
      matrix using low 5 to 10 ? A beam current, the FFB system appears
      to be more stable. Scott Higgins, Pete Francis and Yan worked out
      the FFB subtleties yesterday.

      There was a spurious, unexplained vacuum event in Arc1 earlier
      this week. The excursion was not significant enough to close
      valves, but three ion pumps reported elated vacuum levels.

          o Parity Quality-Happex
            Happex is not reported any information on parity quality so
            we don't know where we stand on this issue, only that the
            user claims there are more pressing issues. The most
            pressing issue to Happex is the phase advance at the last
            two BPMS, Alex and Jay have some plans to address this at
            Happex's request.
          o Energy Spread-HKS
            Energy spread appears to be reasonably under control. The
            OPS crews need to keep running KREST and chase down
            pathlength errors as much as possible to keep the energy
            spread under control. Without knowing the ?, ? and ? and the
            3C12 dipole the exact value for the energy spread is
            unknown. The Synchrotron Light Interferometer measures 3.5×
            10^-5 , which is an upper limit as long as the ? is near the
            design value of 4m.

            Beam transport to HKS has been routine over the week, no
            issues other than FFB.

          o Hall-B
            Hall-B finished their experiment this morning and will down
            for the next nine days to reconfigure. This experiment
            started in the Winter run this year. For this Fall09 run
            period Hall-B did not achieve its goals.
    * On Call
      Reza was on-call last week. This week it is Geoff Krafft.


    2 2009-09-16 Wed 14:00 Agenda--Notes

We will have a brief meeting after the 1:30 scheduling meeting to 
discuss machine performance, list known problems and possible solutions.

The machine has been running with issues over the week. Hall-A has had a 
variable compton rate and the energy spread is not quite good enough for 
Hall-C. With that said the Halls are "happy" with the beam quality, but 
as the experimental issues subside the accelerator issues will become 
more pressing.

The goal of the meeting will be to develop a plans. Execute the 
non-invasive plans and lobby for time to execute the invasive plans on 
Thursday.

Date: 2009-09-23 09:16:32 EDT

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