8 m Club Meeting

1
Demonstration of Science Observing Modes
AOWG meetingDec. 5, 2003 D. Le Mignant, A.
Bouchez for the Keck AO team
2

• Purpose
• to demonstrate LGS-AO observing modes and
  disseminate accurate information on the
  performance of the system.
• We are
• Proposing a plan to demonstrate LGS-AO observing
  modes
• Proposing a path to shared risk science
  observations in 2004B.
• Soliciting and welcoming suggestions and ideas

3
Science observing mode demonstration plan

• Define most important observing modes
• Focus on the observing modes for which the
  functionalities are in place
• For these modes, engineering targets will be
  chosen by AO team.
• Analysis of these engineering data may be done
  through collaborations, but tools and results
  should be made available to community.
• Technical and performance results, techniques,
  and tools to be distributed to community.

4
Risk levels

• Demonstrating LGS-AO observing modes is closely
  related to
• LGS-AO development priorities
• LGS-AO characterization and performance effort

• Assign risk levels to various observing modes by
  Feb. deadline
• Low risk demonstrated, some inefficiency.
• Moderate risk Functionalities in place, not yet
  demonstrated.
• High risk Functionalities not yet in place or
  pushing performance limits.

5
Main criteriaand risk levels expected in Feb.
2004

• Low risk
• TT star V lt 16
• Dither with laser on optical axis
• TT star lt 30 from center of NIRC2 FOV
• Integration up to 10 min.
• Vertical Angle mode
• Moderate risk
• TT star V lt 18
• laser kept on target during dither, throw lt8
• Integration up to 20 min.
• High pointing accuracy (5-10milli-arcsec)
• Position Angle mode
• Elevation variation gt 20deg. or fast rotating
  pupil
• High risk
• TT star V gt 18
• Moving TT stars
• Differential atmospheric refraction correction

6
Example AGN imaging and spectroscopy AGN mag.
18.2 TT star 16.4 _at_ 10 arcsec

• Many potential ways to observe this target..
• Possible path to demonstrate both the feasibility
  and the performance
• closing loop on V 16.4 star
• off-axis observing with high accuracy TSS dither
• PA mode with TSS dither
• performance for 10min integration
• TSS dither with LGS kept on target
• ? then demonstrate the feasibility of observing
  an AGN using such setup
• and in parallel
• TT performance on extended/faint objects
• on-axis observations with TSS dither while laser
  is kept on target

7
Proposed strategy for 2004A (11 eng. nights)

• Some fraction of each night reserved for
  subsystem testing, e.g.
• Laser pointing.
• Low-bandwidth wavefront sensor tip-tilt sensor
  optimization.
• LGS-AO characterization and performance
• to be presented and discussed today
• Observing mode demonstration
• comes after sub-system testing and validation
• Need backup programs for weather/laser
  contingency.
• Could carry out observatory staff research
  programs.
• Or, could call for NGS mini-proposals.
• Web-based proposal, with very detailed list of
  observing parms
• Service observing lt 3 hours for each project
• Which proposal is activated depends on
  conditions.

8
LGS observing modes in 2004 B

• LGS-AO engineering will continue in 04B
• more functionalities/automation fed into the
  system
• more characterization/performance
• more demonstration of observing mode
• Shared-risk science
• We must commit to performance criteria in Feb.
  2004.
• Led by outside PIs, possible collaboration with
  LGS-AO team.
• If something breaks, engineering is first
  priority.
• How to optimize the return from shared-risk
  science?
• Shall we decline high-risk science projects?
• Shall we have NGS weather contingency proposals
  ranked by UC/CIT/UH TACs?
• Shall we suggest a limit on the number of
  observing nights for both NGS and LGS in 2004B?