[Halld-pid] Time-of-Flight Meeting Minutes, November 7, 2013

[Mark Ito]

Folks,

Find the minutes below and at 
https://halldweb1.jlab.org/wiki/index.php/GlueX_TOF_Meeting,_November_07,_2013#Minutes 
.

   -- Mark
________________________________________________________________________________

GlueX TOF Meeting, November 07, 2013
Minutes

    Present:
      * FSU: Sasha Ostrovidov
      * JLab: Hussein Al Ghoul, Eugene Chudakov, Paul Eugenio, Mark Ito
        (chair), Aristeidis Tsaris, Beni Zihlmann
      * Northwestern: Sean Dobbs

    Find a recording of the meeting [32]here.

TOF Delivery

    Find some photos [34]here.
      * Paul, Hussein and Aristeidis drove 6 crates of modules up from FSU
        and stored them in the ESB yesterday. They inspected modules in two
        of the crates and they look like they made the trip totally intact.
        Each crate holds 8 modules. These are all standard modules. There 5
        more crates to transport. Those will come in a couple of weeks.
      * FSU also delivered the the steel shields that were made by the
        machine shop there. This is all of them.
      * When the last 5 crates of modules are transported, FSU will also
        bring the collars, stand-offs, and Swiss cheese blocks. All of the
        parts are made except for the stand-offs, which are near complete.
      * They will also bring equipment to test the modules here, including
        a crate, HV supply, and a scope.
      * FSU would like to have a small locker or set of shelves in the Hall
        or Counting House to store tools, such as the tube removal device.
      * We will check with Tim to make sure that floor space in the Hall
        for assembly is in his plan. [Added in press: it is.]
      * Congratulations to FSU for achieving this important milestone!

Module Testing

    Sasha reported that the testing of all 92 modules is now complete,
    including the half-length and half-width modules, of course. See
    [36]his web page for details. He covered the following topics:
      * Status of TOF module tests
      * HV balancing for short modules
      * Issue with time walk correction fit

Calibration

    Sasha led us through the talk he gave last year on calibration,
    outlining the thinking at that time. See [38]his slides for details.
    The plan is in six steps
      * Step 1: TDC / ADC calibration
      * Step 2: PMT gain balancing and monitoring
      * Step 3: Time-walk corrections
      * Step 4: Single-paddle left/right adjustment
      * Step 5: Paddle-to-paddle timing offsets
      * Step 6: Fit of TOF time to RF time

    Sean is pushing each detector group to list the sets of calibration
    constants that will be needed. We can then work backwards to the
    procedures necessary to measure these constants. Sasha volunteered to
    draft a list for us.

    Retrieved from
"https://halldweb1.jlab.org/wiki/index.php/GlueX_TOF_Meeting,_November_07,_2013"

References

   32. http://cc.readytalk.com/play?id=7rm92
   34. 
https://plus.google.com/photos/114699847528520444979/albums/5943986330056690545
   36. 
https://halldweb1.jlab.org/talks/2013-4Q/Status%20of%20TOF%20module%20tests%20%28Nov%207,%202013%29.html
   38. https://halldweb1.jlab.org/talks/2013-4Q/tof-2012-10-calib.pdf

-- 
Mark M. Ito, Jefferson Lab, (757)269-5295, marki at jlab.org