[Halld-pid] Start Counter Meeting Minutes, April 4, 2013

[Mark M. Ito]

Find the minutes below and at 
https://halldweb1.jlab.org/wiki/index.php/GlueX_Start_Counter_Meeting,_April_4,_2013#Minutes 
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GlueX Start Counter Meeting, April 4, 2013
Minutes

    Present:
      * FIU: Werner Boeglin, Eric Pooser
      * JLab: Mark Ito (chair), Beni Zihmann

Announcements

    Mark talked to Youri Sharabian about how he bent the scintillator for
    the CLAS start counter. Turns out he had Eljen do all of the shaping of
    the bars, both bending and milling of the edges. His contact at Eljen:
    Chuck Hurlbut.

Construction News

Scintillator Manufacturing

    Eric reported that Eljen has finished manufacturing five counters with
    a precision bend. Chuck Hurlbut explained the procedure:
      * Clamps of polished aluminum are used.
      * Scintillator is heated 2 inches beyond bend region.
      * The clamp is heated as well.
      * The system allowed to cool, enough to handle.
      * The scintillator bar is turned on its side and placed on a surface
        with a drawn line that indicates the proper shape and then allowed
        to cool for 24 hours.
      * If the bar does not hold its shape, heating and clamping is
        repeated.

    Eljen has internal discussions on packaging the bars for shipment. They
    will apply a clear light-tack adhesive film to all of the counters. The
    idea is to leave this film on the broad surfaces while the edges are
    machined at McNeal.

    Eric is waiting to see if McNeal has received the bars. In the
    meantime, he has been discussing minor details on the contract with
    them including packaging and handling procedures. The total cost for
    the complete detector should be about 4 k$.

Test Stand

    Eric walked us through [21]drawings of the stand designed for
    acceptance testing of incoming scintillator bars. There is a fixture
    with a Sr source and trigger scintillator that can be moved to
    reproducible positions along the scintillator under test. There is also
    an [22]XYZ motion stage to hold the SiPM detectors. The entire
    structure will be inside a dark box.

    Eric would like to have the stand constructed and working before the
    five bars arrive from McNeal. Machining will be done in the FIU shop by
    Carlos Ortega.

Contract

    Ludmilla Ettiene sent the technical proposal to JLab Procurement. The
    terms and conditions are still being worked on at FIU. Sponsored
    Research has received comments from Legal, but nothing major. Werner
    has been asked to respond to a few questions. JLab should recieve the
    complete package by next week sometime.

    Retrieved from
"https://halldweb1.jlab.org/wiki/index.php/GlueX_Start_Counter_Meeting,_April_4,_2013"

References

   21. https://halldweb1.jlab.org/talks/2013-2Q/Test_stand.pdf
   22. 
https://halldweb1.jlab.org/talks/2013-2Q/Newport_XYZ_Translation_Stage.JPG

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