Joint Plenary for Forecasting/Reference Design

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Notes

Questions: What plans for instrument systematics modeling on the decadal timescale and beyond? What instrument parameters values should we use, guided by simulations & experience?

  • Complementary performance-based and ab initio forecasting
  • Write down specs for eg. bandwidth, NET, etc, justified by demonstrated performance
  • Need single reference document for all of these (wiki page? google sheet?)
    • Organize by subsections of CDR reference design chapter
    • Incorporate requirements & achieved values from S3 experiments
    • Include links to S3 references
    • "Are we done? What next?"
  • Cascade diagram progressively decomposing each element
  • For many boxes there are uncontroversial numbers that can be used as the starting point
  • On which parameters do we need to do better than S3 to achieve our goals?
  • CDT framework provides maxima for eg. additive contamination
    • see CDT report appendix A, wiki links & forecasting paper in progress
  • Track propagation of systematic from source to power spectra to identify scaling with eg. number of detectors
  • What's going to be hard?
    • Beams, beams, beams & beams
    • Cross-talk
    • Bandpass mismatch
    • Polarization calibration
    • Readout electronics stability
  • Big arrays won't necessarily integrate down as we might hope
  • Prioritize effects that need to be addressed - things that can either be checked-off fast or are highest risk/reward
  • Need to avoid telecon proliferation
    • Small group to lay out spreadsheet (Zeesh, Colin, ... ) & call telecon(s) only as needed
    • Add tab to John Ruhl's spreadsheet & require login to edit
    • Identify key contact point(s) in each S3 experiment
  • Detector fab questions:
    • Current approach scales from B/K - how representative of S4 fab will this be? Yield, scatter, ...
    • Need flow down to factors that inform NET, including spread (with frequency)
    • Use best B/K as credible target
  • Identify things could be legitimate improvements
    • Base temperature
    • Increased duty cycle from dilution refrigeration
    • Hold these as margins?
    • Detector count is the special case!