<Keck NGAO Team Meeting #4>

8:00a - 5:30p (Hawaii Standard Time)

Monday, January 22, 2007

Hualalai Conference Room, WMKO Headquarters, Waimea, HI

Telecon attendees: 877-280-4645 passcode 540030 Videoconference IP: 128.171.99.70

Directions: Kamuela (Waimea) town map (.html) and Big Island map (.html)

Goals (Tentative):

• Review initial operations architecture
• Review initial NGAO performance and efficiency budgets
• Review recent trade studies
• Discuss needs for 07A on-sky engineering time
• Review instrumentation working group progress

Agenda (Tentative):

• 7:45 am Refreshments
• 8:00 am Management Report (Wizinowich) Project Report #1
  • Review study overall progress, progress against milestones, and summary financial situation
• 8:30 am Systems Engineering Group Report (Dekany)
  • Review overall progress, interactions with science and instrumentation teams, and other 'big picture' SD phase technical issues.
• 8:40 am Science Requirements: Contiguous Field of View (Max) Max_ContigFields_v1.ppt * Assemat_FALCON_MNRAS.pdf: Paper on FALCON MOAO System
  • Discuss the requirements for contiguous field of view, as developed for each of the driving science cases. Review alternative techniques and competing capabilities, including spacecraft.
• 9:10 am Science Operations (Le Mignant) (NGAOmeet070122sciops.ppt)
  • From the WBS Dictionary (3.4.2.1): Define the overall architecture, the method and design the interfaces for operating the sub-systems of the NG AO-instrumentation. Here AO-instrument refer to AO, laser, SC, science instrument, etc.
  • Discuss operations team's strategy for structuring the remainder of the SD phase tasks under 3.4.2.1
• 9:50 am System Requirements Document (Release 1) (Wizinowich) Requirements
• 10:05 am Break
• 10:20 am Initial Performance Budgets (Dekany) Performance Budget Update (.pdf))
  • From the WBS Dictionary (3.1.1): Development of systems level engineering budgets for a variety of astronomical performance metrics, organized around key observing scenarios. The level of detail available to each budget will depend on the state of the art, the resources dedicated to budget generation during the SD phase, and astronomical user experience. All performance budgets should parameterize the performance behavior versus the corresponding sky coverage fraction. (when appropriate, coverage levels of 5, 30, and 90% should be assumed).
  • Presentation material to be prepared by:
    • • Astrometric Accuracy (Cameron)
      • Background and Sensitivity (Bouchez) background and transmission (.ppt)
      • Encircled Energy (Gavel) Ensquared Energy (.pdf)
      • High-Contrast (Flicker) HC_update.ppt
      • Photometric Precision (Britton)
      • Polarimetric Precision (Ireland)
      • Wavefront Error (Dekany)
• 12:00 pm Lunch
• 12:50 pm Trade Study Report: Telescope Wavefront Errors (Neyman) (Neyman.ppt)
  • From the WBS Dictionary: Review new data on the telescope static and dynamic wavefront errors. Determine how and whether NGAO can correct for these errors. Determine the performance benefit of a large LOWFS patrol field to enable use of the brightest possible NGS. Consider whether a separate sensor outside the NGAO FOV would be useful for measuring/correcting the telescope errors. Complete when impact on current Keck LGS AO system understood and impact on NGAO reviewed.
• 1:30 pm Trade Study Report: LGS Wavefront Sensor: Type and Number of Subapertures (Velur) (HOWFS_type_&_#_of_subaps.ppt)
  • From the WBS DIctionary (3.1.2.2.6): Consider alternative WFS designs (e.g. Shack-Hartmann vs. pyramid) for different laser pulse formats. Evaluate and compare the advantages of e.g. short pulse tracking using radial geometry CCDs and mechanical pulse trackers. Complete when LGS WFS requirements have been documented.
  • From the WBS Dictionary (3.1.2.2.7): Consider the cost/benefit of supporting different format LGS wavefront sensors (e.g. 44 subaps across, vs. 32, vs 24.) Consider the operational scenarios required to meet science requirements in poor atmospheric seeing or cirrus conditions?
• 2:10 pm Trade Study Report: Low-order Wavefront Sensor: Architecture, Type, and Number (Clare, Flicker) (Kellner_status.ppt) (Clare.ppt)
  • From the WBS Dictionary (3.1.2.2.9): Consider the cost/benefit and technical maturity of MEMS-based correction within the LOWFS, using MOAO control techniques. Include consideration of additional metrology systems required, if any. Compare with cost/benefit of MCAO system to provide tip/tilt star sharpening. Complete when LOWFS requirements and sky coverage estimates have been documented.
  • From the WBS Dictionary (3.1.2.2.10): Perform a cost/benefit analysis for the optimal type, waveband, and number of tip/tilt and tip/tilt/focus low-order WFS. Complete when LOWFS requirements and sky coverage estimates have been documented.
• 2:50 pm Discussion (led by Dekany): On-sky experiment needs for 07B
  • Discuss progress in the key NGAO risk areas and identify the top priority risk mitigations requiring on-sky Keck LGS engineering time.
  • Assign responsible experiment PI's and set deadline for distribution of experiment plan for review
• 3:20 pm Break
• 3:40 pm Instrumentation Working Group Report (Adkins, Moore) (Instrument-Reuse-Questions-012407_2.ppt)
  • Overall status, questions for the science team.
• 4:10 pm Discussion: Upcoming tasks and milestones (Wizinowich)
  • A review of actions arising from this meeting was made. (During the sys eng report, Dekany described the Team Meeting #5 trade studies and coordination thereof.)
• 4:45 pm General Discussion (All)
• 5:30 pm Adjourn

• Evening NGAO Function - TBD (6:30p)