[Halld-pid] Notes from JLab/Hamamatsu phone conference, Hall D Start Counter Readout

[Mark M. Ito]

Folks,

Find the notes at 
https://halldweb1.jlab.org/wiki/index.php/Conference_Call_with_Hamamatsu_Representatives,_January_5,_2012 
and as text below.

If I misstated anything, please let me know.

   -- Mark
   _____

Conference Call with Hamamatsu Representatives, January 5, 2012

    Present:
      * JLab: Fernando Barbosa, Mark Ito, Elton Smith, Tim Whitlatch, Beni
        Zihlmann, Carl Zorn
      * Hamamatsu: Earl Hergert, Samir Patel

    Mark introduced the general problem of start counter read-out, reviewed
    the motivation for using SiPM's as the photo-detector and the geometric
    constraints for mounting them. Reference was made to drawings posted on
    the [5]Start Counter Cheat Sheet.

    We quickly eliminated the possibility of using raw dies from Hamamatsu
    and packaging them ourselves at JLab or at a sub-contractor. We do not
    have the facilities to do wire bonding. Hamamatsu has confidence in
    their in-house process.

    Werner Boeglin had drawn up a concept where a 5×1 array of 3×3 mm
    sensors are arranged at the end of the scintillator. No such packaging
    is listed in the catalog and in real life the package edges and
    inter-die spacing would have to be accounted for.

    Other options were also discussed including having Hamamatsu do the
    wire bonding on a JLab supplied package, and using other die sizes, in
    particular 4×4 mm.

    We coalesced around Earl's recommendation of using 4 SMD-type 3×3 mm
    devices in a row. The radius of the counters would have to moved
    slightly outward from Werner's nominal 73 mm to allow enough width for
    package placement, but we thought that could be accommodated. This has
    the advantage of using a standard package and would cover about 75% of
    the scintillator face. This design would use 30×4 = 120 devices.

    Carl suggested that we consider using the 100 micron pixel device to
    compensate for the loss in area coverage. It would have higher PDE and
    gain than the other sizes, but higher noise as well.

    We requested quotes from Hamamatsu for a small quantity to do
    prototyping:
      * 10 pieces, 3 × 3 mm, SMD package, 100 micron pixels
      * 10 pieces, 3 × 3 mm, SMD package, 50 micron pixels

    Also we requested a quote for a complete order for the new reference
    configuration for budgetary purposes.
      * 150 pieces, 3 × 3 mm, SMD package, 100 micron pixels
      * 150 pieces, 3 × 3 mm, SMD package, 50 micron pixels

    Fernando had questions about special conditions for the re-flow process
    for these devices. Hamamatsu agreed to send that information to us.

    Hamamatsu will look into the availability of 4×4 mm dies.

    Tim told us he would get us 3-D drawing of the region with the updated
    dimensions.

Retrieved from
    
"https://halldweb1.jlab.org/wiki/index.php/Conference_Call_with_Hamamatsu_Representatives,_January_5,_2012"

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