[Halld-pid] Start Counter Meeting Minutes, November 29, 2012

[Mark M. Ito]

Find the minutes at

https://halldweb1.jlab.org/wiki/index.php/GlueX_Start_Counter_Meeting,_November_29,_2012#Minutes

and below as text.
___

GlueX Start Counter Meeting, November 29, 2012
Minutes

    Present:
      * FIU: Werner Boeglin, Puneet Khertarpal, Eric Pooser
      * JLab: Eugene Chudakov, Chuck Hutton, Mark Ito (chair), Beni
        Zihlmann

Review minutes from previous meeting

    We reviewed the [20]minutes from the November 15th meeting.

    FIU has found sufficient HV channels to get by for now. Another CAEN
    module is on order.

Counter shaping and polishing at McNeal

    Eric went through an abridged version of the presentation he gave for
    the CEO of McNeal on recent experience with the scintillator. See
    [21]his slides for details. He showed evidence for degradation of the
    attenuation length that is likely due to mishandling at McNeal.

    Werner also points out that we should research how the heating and
    bending may affect scintillator long-term quality even if mechanical
    handling is done properly. He will talk to Eljen about this.

SiPM read-out status

      * Eric mailed the broken ST-2 board to Fernando Barbosa. The gain
        measurement still needs to be done before Fernando finalizes all of
        the component values.
      * Eugene reported that a shipment of SiPMs from Hamamatsu came in
        this week. Some of those can be used for more start counter
        read-out cards.
      * FIU is installing a new version of CODA, version 3. They are
        getting help from David Abbott and things are going well.
      * FIU could use a few more discrimintator channels. JLab will look
        into getting one of the new VME discriminators for them.

Light collection study status

    Puneet reported on progress with his studies. See [22]his wiki page for
    details and plots. He has studied light output as a function of
     1. distance from a "track" to the end with light detection,
     2. microscopic surface roughness on the counter edges, and
     3. counter thickness.

    Faces are assumed to be smooth. He sees very little dependence of light
    yield as a function of thickness. This is at odds with experimental
    experience a couple of years back with counters of varying thickness.

    Plans for further study include adding roughness to the faces and a
    study of cross-talk between adjacent counters in the absence of
    wrapping[?].

Contract

    Mark sent Werner an example of a successful proposal he can use as a
    model for the FIU submission.

    Retrieved from
"https://halldweb1.jlab.org/wiki/index.php/GlueX_Start_Counter_Meeting,_November_29,_2012"

References

   20. 
https://halldweb1.jlab.org/wiki/index.php/GlueX_Start_Counter_Meeting,_November_15,_2012#Minutes
   21. https://halldweb1.jlab.org/talks/2012-4Q/st_talks/Nov_29_2012.pdf
   22. 
https://halldweb1.jlab.org/wiki/index.php/Start_Counter_Simulations#nov-29-2012

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