[Halld-pid] Time-of-Flight Meeting Minutes, January 31, 2013

[Mark M. Ito]

Folks,

Find the minutes at

https://halldweb1.jlab.org/wiki/index.php/GlueX_TOF_Meeting,_January_31,_2013#Minutes

and below.

   -- Mark
   __

GlueX TOF Meeting, January 31, 2013
Minutes

    Present:
      * FSU: Sasha Ostrovidov
      * JLab: Eugene Chudakov, Chuck Hutton, Mark Ito (chair), Tim
        Whitlatch, Beni Zihlmann

Mini-TOF Construction

    Module assembly should start today.

    There was an issue bolting the mini-TOF structure to the floor, but
    that has been solved.

Light Guide Production

    Two students are now working on polishing light guides. Along with
    improvements in the procedure the rate of progress has doubles
    recently.

PMT Testing

      * All 194 PMTs have been received from Hamamatsu.
      * 160 have been tested, with single photoelectron peaks observed from
        an LED source.
      * 130 have been tested with the "americium source".
      * About 100 of them have been tested with the "cesium iodide source".
        Two of the tubes show strange spectra.
      * LED testing should be done in a couple of weeks.
      * All testing should be complete in three to four weeks.

Scintillator Testing

    The first article scintillators have been tested using a UV LED.
    Attenuation lengths have been measured for all six counters: 2
    standard, 2 half-width, and 2 half-length. See [25]Sasha's wiki page
    (standard GlueX username and password if needed) for an explanation 
of the
    procedure, plots, and results (click through to the counter-by-counter
    pages). The standard and half-length counters have a measured
    attenuation length of about 155 cm and the half-width counters give
    about 90 cm, with consistency among each of these two groups. Sascha
    noted that the bulk attenuation length is supposed to be 260 cm, so
    these results seem reasonable.

Collaboration Meeting

    Both Paul and Sasha will be coming up from FSU for the meeting.

Readiness Review

    We are aiming for late February or early March. Beni, Chuck, and Bruce
    Lenzer will travel to Tallahassee. Mark, Eugene, and Tim will
    participate via video conference.

    Retrieved from
"https://halldweb1.jlab.org/wiki/index.php/GlueX_TOF_Meeting,_January_31,_2013"

References

   25. http://hadron.physics.fsu.edu/TOF/database/SCIN_led.html

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