Attending: Shaul, Jamie, Al, Brad, Amy, Mike
Notes: Qi Wen + Shaul

Agenda:

• Brief review of last week + Packing of optical systems (UMN)
• Update on shields? (JPL)
• frequency bands + multi-chroics

Actions:

• Brad will revisit EPIC-IM sidelobe analysis, will report next week on what is required to fire up the analysis for CMBP.
• UMN follow up on coma corrections for the Dragone telescope
• UMN/Brad check on sidelobes for open Dragone system; Amy will check whether there is anyone at JPL to run GRASP
• Amy to provide feedback on sun-shield style, geometry, and explore deployable shields

Notes:

• Shaul gives brief review of last week
  • there is consensus to proceed with 1-m class reflector system
  • Brad will revisit EPIC-IM sidelobe analysis and give a report next week.
• Mike says they are exploring coma correction for the Dragone design that can increase DLFOV. Shaul says UMN is following this path as well. He points to a paper by him and Marrone in which they investigated these corrections awhile back.
• Open Dragone as an option: better baffling, but at the expense of a larger primary. Jamie asks about DLFOV relative to the crossed Dragone and whether sidelobes have been investigated. Shaul says DLFOV is comparable to the Crossed design. No investigation of sidelobes have been done yet.
  • Brad can do far sidelobes of the open dragone system; Amy will check whether there is anyone at JPL to do that as well.
  • Jamie is concerned about the sidelobes. The analysis showed that it was OK for EPIC, but just barely.

• Packing of optical system: Shaul shows a trade-off between aperture size and scan angles, alpha, beta without deployable shields. There is about 7 degrees gain toward larger alpha per 20 cm diameter reduction on the primary mirror for a crossed dragone design.
  • Jamie asks whether COBE had deployables? Al will check.
  • Jamie gave design of possible deployables to Amy; she will check with JPL engineers.
  • Shaul asks about the style of V-groove shields. Shall we use the book style or the cone style? Amy will respond.
  • Amy/Jamie say that a focal plane far from the bus is a non-starter

• Frequency bands selection
  • Shaul describes a nominal band selection for the Probe with 25% bandwidth
  • Jamie says bands can be broader to get more s/n; Shaul says the bands were chosen to 25% because we are using multi-chroics. But perhaps they can be broader.
  • Mike says that the AdvancedAct technology gives an octave of bandwidth
  • There is broad agreement that the focal plane needs to have the flexibility to accommodate a number of technologies.