2016/05/24 (Tuesday)

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Titus link to CDMS2 spool and other drawings

• 100mm housing
  • Crown base height: 0.089
  • Crown total height: 0.089+0.145
  • Bottom to slot bottom plus crown base: 0.307
  • Slot thickness: 0.119
• 3“ X 1cm housing
  • Bottom to slot bottom: 0.217
  • Slot thickness: 0.100 (a little off from drawings, should be 0.120, about 1/64 too small)
• 3” X 1“ housing
  • Crown lip height: 0.148
  • Bottom to slot bottom plus crown base: 0.301
  • Slot thickness: 0.122
• Old tower spool (ZB-2)
  • Spool-crown spacer thickness: 2 X 0.010
  • Height 3.475
• Old tower
  • Pins to top edge: 0.624 + 0.040/2 = 0.644
• New tower spool (IZ5)
  • Height 3.361
• Old tower
  • Pins to top edge: 0.626 + 0.040/2 = 0.646
• sCDMS Soudan Side Coax pin separation height
  • Short: 4.540-0.016/2
  • Medium: 5.617-0.016/2
  • Long: too long for calipers. 6 11/16

Making sense of side coax lengths

We can compare CDMSII-era hardware (1 cm thick detectors in a stack of six) with our 100mm setup (detector in first or second position) and with the sCDMS Soudan hardware (1” thick detectors, stack of three).

In all three we assume the same Tower dimensions, Crown thickness, and Housing bottom-edge-to-pins distance. (The last of these is confirmed from drawings for 1cm and 1“ detectors, but I couldn't find a 100mm drawing, should confirm).

I couldn't find any technical drawings for spools. I did find technical drawings for the CDMSII side coaxes. I inferred the CDMSII spool height from the side coax lengths. It seems to be in good agreement with measurements of our old tower spool. Not surprising - this is probably old CDMSII hardware.

Since all heights agree between CDMSII and our 100mm setup for the first detector position, it seems that if we have a detector in the first position we can use a CDMSII Position 1 side coax. If we have a detector in the second position, the pin separation distance comes out to be 0.012” longer than a CDMSII Position 4 side coax. Thus it makes sense to use a thin spacer to lengthen the spool. We seem to have been using two 0.01“-thick spacers, which seems a bit more than needed.

With sCDMS Soudan, it seems that the spool height was changed. Caliper measurements show it is about 0.12” shorter than the CDMSII spool. So the sCDMS Soudan P1 side coax length is significantly shorter than the CDMSII Position 1 side coax. It turns out the sCDMS Soudan P2 side coax is very close to the length of the CDMSII position 3 side coax. The sCDMS Soudan P3 side coax is a bit longer than the CDMSII position 5 side coax.

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