July 26, 2019 FCAL Insert Design Meeting

Meeting Time and Place

Friday July 26,2019 1pm At Jefferson Lab, room TED 2504

Discuss 40x40 vs 32x32 crystal assembly
- 32x32 crystal matrix layout Media:32x32_crystal_matrix_2D_layout.pdf
- 40x40 crystal matrix layout Media:40x40_crystal_matrix_2D_layout.pdf
- Decision to pre-measure stacks of crystals and the existing FCAL to determine bottom row offsets
- Shimming of row above crystals may be needed
Discuss installing Rohacel US of crystals to fill hole and support the lead glass blocks
- Rohacel properties Media:Rohacel cut sheet.pdf
- Radiation Hardness https://p25ext.lanl.gov/phenix/mvd/notes/1997/PHENIX-MVD-97-5/radiation.html
Discuss Tungsten absorber
- How many crystals does it cover?
- How to support it and the blocks above
Monitoring System
- Is acrylic sheet good enough for crystals?
How were original FCAL lead glass modules stacked?
- Matt Shepherd stated that they were rotated 90 degrees every other one and bottom row was shimmed as required.
- What should the shim material be
3D Screenshots
- Overall Iso View Sept 2018 Media:Iso.png
- Cooling Iso View Sept 2018 Media:Cooling Iso.jpg
- Cooling-compression Plate Iso View Sept 2018 Media:Cooling-compression Iso.jpg

We will go with the 40x40 matrix for the design, we will have to shim if the install changes to 32x32
Need to define rohacell
Need to define monitoring system
Need to define tungsten absorber geometry
Need to perform heat load calcs
Need to define cable management system
Need to define shim material