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Agenda

  • Operations
    • Run 68: n,gamma coincidence with S101 (aka HV#4, Si HV prototype)
      • 1K Pot working well now, cooldown was fine
      • Slow cooling to base like last time we ran S101. First day → 51.3 mK at tower, 5 days later down to 38.8 mK
      • Trouble biasing at first because new voltmeter was grounding the test resistor
        • Nick fixed this with home-made cable
        • this voltmeter (for V_test) communicates with LabVIEW, as does the meter for V_bias. So we can log bias and leakage.
      • Started IbIs measurements to find good QET settings. Also see if there are variations with bias.
      • Confirmed PuBe source is available for us through end of August, minus a day for TA training (which may have already happened).
      • have a few options for source position & trigger mode
  • Lab infrastructure
    • He-3 circulation pumps
      • still need to send back-up He-3 pump to Oerlikon/Leybold for service/repair
  • Processing and Analysis
    • Run 67 (re-run of USD1)
      • starting to work on impact ionization model
    • Run 65 (Si 150mm 5Q 1/2-vacuum-interface)
      • 150 mm paper submitted to NIM A. Posted to arXiv.
    • LIPs search using Run 66 GeHV data.
    • Need to start Phonon Collection Efficiency paper (HV2, HV4, iZIP pathfinder)
    • Run 62 (HV#4, Si)
      • planning to work on low-energy calibration, in prep for Run 67
    • Run 63 (Ge iZIP pathfinder)
      • need to analyze Cf data
  • Old/continuing items:
    • exploring ideas for improvements without upgrade: sidewall sources?
    • Run 62 (HV#4, Si) post-mortem: two “bad” channels seem not to be wiring problems, maybe the problem is on the detector (photos)
    • Lab infrastructure
      • plans to try to improve helium recovery
        • add length of copper tubing to recovery line, to warm helium on the way to the meter. We have used it and it seems to do something. But no indication yet that it is improving recovery.
        • maybe try to recover helium while waiting for the transfer stick to cool before hookup
      • Update on He recovery efficiency, slow transfer test
      • DAQ and data pipe
      • DAQ upgrade - discussed with Bruno about IbIs tool development
      • Data storage and backup:
        • Need to copy all Run 60 and some Run 61 data to SLAC
      • Autoprocessing and data organization development:
        • currently autoprocessing suspended, no “official” processing for Runs 60, 61, 62
        • clean up database - some info missing. Consider adding additional info
    • Possible plan to modify DCRCs (resistor swap) so we can increase front-end gain, improve IbIs (suggestion from Bruno)