Telecon 20180117

Attending: Toki, Brian, Al, Qi, Karl, Shaul, Tom, Kris, Graca, Ed

Notes by : Karl

• Priority items for the next 2 months (next TeamX) and 5 months (PICO workshop) (all)
  • review TeamX results, prep for next TeamX-I, M
  • review technology development items for report
  • review integration + testing plan
• TeamX (somewhat new) Optics, and Focal Plane (Karl)
• Status of GRASP (Brad)

Priority items for the next 2 months (next TeamX) and 5 months (PICO workshop) (all)

• draft report exists. final version for distribution should be in ~2 weeks.
• PICO was fine on engineering and costs, no showstoppers.
  • Instrument was $180M, agreed with goal.
  • Cooling was majority, $90M. Other details to come.
• March TeamX is instrument and mission. These results go directly to Decadal panel.
  • We should consider integration and testing. Some slides on this were submitted to last TeamX (Tomo, Bill Jones) but not part of evaluation yet.
• May workshop in Minneapolis to plan for report and Decadal.
  • What tech development do we want to highlight for the final report? Some probes are planning far in the future with requirements for significant tech developement. We may want to discuss some.
  • KG: Communication bandwidth? Are we still bandwidth limited.
    • SH: With 12k detectors, Nyquist sampling each pixel at the appropriate rate for its smallest beam, 4 hrs of DSN, and 150 Mbps there is no problem. Roughly a 2x margin still.
      • Al: What antenna and band? SH: Don't know. We'll revisit details in 1 week with Amy.
    • KG: Does antenna tracking limit us?
      • Ed: This will be steerable antenna, but mass can impact precession, spin, craft dynamics etc. There is a cost tradeoff to be accounted for.
  • KG: Large (~1m) HWP for space.
    • Toki: and AR coatings for them.
  • KG: lowering the cost of cooling.

TeamX (somewhat new)Optics, and Focal Plane (Karl)

• Optics from Jim McGuire using Zernike polynomials and further optimization are more compact with larger FOV.
  • To do: Calculate FOV and compare to designed focal plane, check if clearance between incoming rays and focal plane is sufficient.
• Focal plane redesign in a work in progess.
  • Goal of simplifying focal plane (all 1 size of wafer if possible) to reduce cost.
  • Complexity (even visual complexity) = cost, at TeamX.
  • To do: pack single type of A, B wafers to fill the shown white space.
  • KG: Anything special about hexagons?
    • Toki: No. Also could try packing rhombi. Hexagons are most efficient use of a circular wafer, but rhombi fine as well. Packing efficiency should be the main driver here.

GRASP update delayed to next week