Meeting time and location= 1:00 pm EST (JLab time) F228

Connection instructions

We are using BlueJeans Video/Audio conferencing. Our meeting ID number is 370588741. Click "Expand" for more details.

Make sure you have created a BlueJeans account via your JLab CUE account using this link:
- http://jlab.bluejeans.com (You should only need to do this once)
If connecting via Web Browser: click this link (no passcode is needed):
- https://bluejeans.com/370588741
If connecting via Phone: Dial one of the following numbers and then enter the meeting ID above and hit "#" or "##"
- Dial: 1 888 240 2560 (US or Canada only)
- or, List of International Numbers
If connecting via Polycom unit:
- Dial 199.48.152.152 or bjn.vc
- Enter meeting ID above

Agenda

Attendees: Wolfgan, Josh, Simon, Sasha, Zisis

Magnetic field studies more or less complete
- From last time: Sasha suggested moving FCAL assembly 35 cm downstream to reduce field in PMT region for lead tungstate
  - Could stack lead glass blocks that we remove from the central region in the outer radius to improve acceptance
- Studies with 350 micron mu-metal shielding + iron housing look promising -- added additional 50 micron mu-metal
  - For 60 Gauss longitudinal external field -> 2 Gauss in center of housing+mu-metal shield
  - PMT response in central position of 3x3 array flat up to about 40-50 Gauss longitudinal field
  - No saturation of mu-metal seen
  - Currently using 1020 steel, could be annealed for ~20-30% improvement
Stacking: insert needs to be well-leveled to distribute load
- Consider adding ~few mm thick plates (above and below insert) in addition to shims
- 1/2-1 FTEs next fiscal year to work on frame and other designs aspects
Cabling/connectors: Hall C style? (lemo for signals?)
Second arm of pair spectrometer now ready for use for parasitic measurements
- Josh working on design for assembly to mount 12 crystals at a time
- Need to consider magnetic field from fringe field of Hall-D solenoid
Zisis can provide summer undergrad students next year, considering putting graduate student of project