====== Telecon 20180620 ======

Attending: Jamie, Brian, Tom, Shaul, Qi

Notes by : Qi

=== Agenda ===
  * {{::20180620_focalplane_mechanicaldesign.pdf|Mechanical design of focal plane }}(Qi) 
  * 2-year, 4 detector, simulated maps available - next steps? (Kris) 
  * {{::picoreport.pdf|Report Writing }}
  * Remaining key open areas: **Thermal Design (JPL)**; Changing telecons to a lower cadence: two weeks?

=== Notes ===
Mechanical design of focal plane
    * Jamie shared the experience with Bicep3 focal plane:
      * heat sink:  gold frames and wires around perimeter of wafer. They found contact resistance is the main issue. Biggest thermal impedance comes from between gold and silicon; at 100mK, conductance is mainly through electrons, pushing harder does not help.
      * 4 clamps push down the wafers, but wafers can still slide; clamps don't short the instruments.
      * In theory, gold wires and bars play the role of RF shields.
    * PICO has a preliminary design, which can be used to estimate the mass already; more details about how to mount wafers on frames are ongoing
    * material of frame: copper vs invar? Jamie: invar has high capacity, large mount of magnetic material
    * bump bonds should be straightforward on PICO time scale 
    * Karl knows the size of TDM, **Qi to find out what Karl has concluded (AI)**

Report writing 
    * page 4, section 3 Instrument is most relevant
    * internal review
    * by the end of August

Thermal design
    * we don't have one yet, JPL is responsible.

**No objection against changing the telecon cadence to 2 weeks.**