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Agenda

  • Operations
    • Run 67 (re-run of USD1) has begun
      • Joseph arrived Tuesday and will leave Tuesday evening
      • double-bonded one detector channel that had unexplained problems (see run 58). Although thinking about it further it seems it was probably a subtle issue with the cold electronics or stripline.
      • Delayed by broken wirebonds on side coaxes - they are very delicate and uncovered on these side coaxes. We'll try covering the exposed part with copper foil after the deinstall.
      • Tower assembled with one Am source above each channel. Tower installed, IVC pumping out.
      • expect to finish in time for April 1 start for n,γ coincidence run
    • n,gamma coincidence run prep:
      • Run Si HV#4
        • use reduced shunt resistances. (Should we replace the SQUET with the “damaged” SQUID?)
        • bare Am source to calibrate. What position?
      • Availability of PuBe source: we will wait until Vlad Pribiag is finished. Last lab is April 30
        • so start run around April 1, configure detector for ~1 month, then begin using source
      • do we understand the n-flux? will it be high enough?
      • Planning to leave out 4K heat sinking
  • 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 65 (Si 150mm 5Q 1/2-vacuum-interface)
    • LIPs search - planning to use Run 66 data, best 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: float DCRCs for symmetric biasing Proposed Scheme, decrease Rshunt in SQUETs (had a look at this, a little hard to set up: SQUET picture), 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)
    • Run 60, 6“ detector paper
    • 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
      • 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)
    • IF (not likely) new DCRC RevC.2 arriving from Bruce in Denver then
      • missing resistors on 3 QET channels, we've ordered some