Agenda

Run 68: n,gamma coincidence with S101 (aka HV#4, Si HV prototype)
- Data not yet looked at:
  - Trigger study data: now processed
  - Hold-time runs at different biases done, haven't looked at them yet
  - Have reprocessed -80V Na data. Used -125V balancing factors, still need to check if those are optimal (if not we should redo it)
- Working on analysis task list
  - have started a simulation instructions page.
  - fiducialization
Run 69 (next run): GeHV n,gamma NR calibration
- PuBe source availability:
  - there is one block of a couple weeks around April when we can borrow it
  - Kevin is amenable to weekend use - it would need to be returned on Sunday for 24-hour activation before Monday classes
- Vacuum interface to reduce noise. Electrode is mostly designed.
  - we will remove all wirebonds from electrode-side. Target 30 mil (0.7 mm) gap.
  - E field simulations
- IR shielding?
- We'll probably try the heat-sinking modification (previous analysis). Note: primary noise is HV-leakage-related, this is a secondary consideration
- Calibration source: plan is to include the smoke-detector Am source in the center, as in the last run.
Future runs
- Future 150mm runs
  - 150mm w/phonons - need to design 600mK rod to accommodate 150mm cans
  - Received 4/3-inch DIBs from TAMU - now we can house either detector for phonon readout (would need to machine faces on 4/3-inch housing for DIBs)
  - S1501 and S1502 sent back to TAMU
  - New ideas from Rupak: how many channels can we run? (8, 12?) Possible “donut+hole” arrangement (active veto).
- Future HVeV runs?
  - Berkeley can help us with a Soudan-style housing mount (3“ or 4”?)
  - then use original tower, can try different heatsinking for colder SQUID card
  - would need to install optical fiber
    - through top or through stripline tube? need vacuum feedthrough
    - Look at Prisca's deuterium lamp/monochromator/filters, glass UV fiber
  - Is PuBe NR calibration feasible?
    - 1×1×0.4 cm^3 is 630× smaller than SNOLAB detector. Anthony estimates 25 events/day (over full spectrum) for Si, 250 events/day for Ge. any chance we could get multiple chips?
    - Nick's idea: sandwich between two 4“ Ge detectors for gamma coincidence (large solid angle coverage)
- Other ideas:
  - run SiHV with Nick's movable Am source (or with multiple Am sources)
  - run SiHV with no 4K heatsinking
  - re-run USD1? do we have any additional ideas to test it?
  - anything else?