Bcal Action Item Tracker

The following persons connected to a phone conference to review the action items that need to be tracked in preparation for CD-3

Online: Kathryn, George Lolos, Zisis, Andrei, Elton, Elke, George Biallas, Chuck, Tim, Christine, Pavols, George Voulgaris.

The Action Item Tracker will be kept up-to-date and used to list items that need attention, goals for addressing them, and when they are closed out. We went over the list and discussed the time scale for addressing them:

• Installation [Jlab]
  • The current plan is to assemble the Bcal outside the magnet and then slide it into the magnet.
  • Dec 1: for Hall D engineering to develop this concept. This will include the concept for how to connect one module to the next.
  • Ideas:
    • (George) Use an O-ring groove in the Al plate to seal light.
    • Tongue and groove technique with screws to pull them together / use a strap to pull the entire ring together.
    • (George) Use Teflon pieces to cover the iron "filler" pieces in the magnet for the support. Can use similar type supports on the outside to create a supporting craddle. Slipping the Bcal into place would not require matching two different schemes for the support.

• Winston cone geometry [Regina]
  • Dec 1: To provide a concept for matching the light guides to the trapezoidal area of a Bcal module, and to consider how to make the assembly light-tight.
  • Next week: Mail a sample Winston light guide to Tim for reference (Tim will send precise address to George).

• Eddy Currents in Bcal (during magnet quench) [Jlab]
  • Need to break the connection around the circumpherence in at least one place (likely the "keystone" module)
  • Dec 1: This will be developed along with the installation procedure.

• Attachement of SiPMs to Winston Cone [Regina]
  • Date? Concept by Regina

• Fiber Specifications [Regina and JLab]
  • Next week: George and Christina will send Elton specifications already written as a basis for the document. (See also one of the Tables in GlueX-doc-866.

• Light Guide Design for Outer Layers [Elton]
  • Next Week: Blake will send Elton code for light guide collection
  • Dec 31: Proposal to include shape and connections to PMTs.

• Length of Bcal
  • Decision to keep length at 390 cm.

• Bcal Timing [Regina]
  • Alex has shown that even sigma=400 ps is useful for pi/p identification for momenta ~ 500 MeV/c
  • Single channel diagram for electronics including splitting of signals