Next Generation Keck AO: Science Case

Contents:

Overview

Overview
  • Subcommittee Charter and Tasks

    Draft charge and tasks for AOWG subgroups:

    The Keck AO Working Group is currently defining the science case and examining performance trade-offs for a next-generation adaptive optics system. This system would be based on a core multi-laser guide star tomography system called KPAO, optimized for high Strehl ratio in the infrared (~70-90%) and moderate Strehls in the visible (~20-40%), perhaps down to H_alpha (6563A). The field of view of KPAO would be narrow (e.g. of order 15 arc sec at K). KPAO’s infrared performance would be a substantial advance over the current Keck AO system, provide a much more stable PSF. In addition, the system will open the door to diffraction-limited optical imaging with Keck’s 10-meter aperture.

    Potential extended missions for the next-generation AO system include wider-field correction in the IR (fields up to a few arc min in diameter) using either multi-conjugate AO or multi-object AO, or alternatively a narrow-field enhancement designed to give higher (and less variable) Strehl performance in the visible. In each of these cases there is added cost and complexity, which must be traded against scientific benefits.

    In order to explore these trade-offs in quantitative terms, the AO Working Group has assembled three subgroups: Extragalactic Science, Galactic Science, and Planetary Science. We are asking each subgroup to identify two to four key topics that can be opened up by next-generation Keck AO, to seek input from other members of the community, and to do the following:

    1. For each of the key topics, establish what the most compelling science case would be for the KPAO "core" narrow-field system, using computer simulations of KPAO performance together with quantitative analysis of issues such as required photometric accuracy, required Strehl ratios, and the effects of temporal and spatial variability of the PSF, surface density of objects on the sky, and number of potential targets.
    2. For each of the key topics, examine the astronomical issues associated with potential extended missions: implementation of wider fields of view (up to a few arc minutes), and enhanced performance at visible wavelengths. Compare the ability for the wider-field IR extension and the narrow-field visible-light extension to address each of the key topics for the subgroups. For the visible-light extension in particular, quantify the science return as a function of observing wavelength and Strehl.
    3. Identify the most appropriate new science instruments, or modifications to existing instruments, to go behind the AO system for each of the key science topics.
    4. Consider the larger context of planned space- and ground-based capabilities.
    5. Coordinate with the KPAO technical working group to identify key instrumental issues and simulation needs.
    6. Present conclusions in a written report, including two to four pages of text on each key science case, as well as an introduction and summary. This should be a document suitable for an independent science review, for example by the Keck Science Steering Committee or an NSF Review Panel.
  • Timeline

    Proposed timeline for developing the science case:

    December Goal: Establish science subcommittees

    • Finalize draft charter and tasks for subcommittees and proposed membership, and timeline.
    • Distribute invitation package to proposed subcommittee members & call members.
    • Membership finalized.

    Jan-Feb Goal: Subcommittees start work & identify science cases to pursue & questions that need to be answered by both science & technical teams.

    • Early Jan: First telecons for each individual science sub-group. Bi-weekly telecons thereafter?
    • AOWG co-chairs should also attend.
    • By 1/27/06, each science team submits a set of technical questions to the technical team via Wizinowich. Technical team to respond within 1 month.
    • The subgroups are encouraged to meet in person at key junctures.

    Mar-Apr Goal: Understand and document science cases. Include interactions with technical team to ensure implications are understood on both sides.

    • 3/30/06 - Face-to-face meeting of science & technical teams.
    • 4/30/06 - Each science team chair submits a draft science case document to AOWG for review.

    May Goal: Unite science cases into a single science case document.

    • 5/5/06 - AOWG telecon used to discuss science cases.
    • 5/30/06 - Final draft science case document distributed to AOWG.

    June Goal: Presentation and approval by SSC.

    • 6/2/06 - AOWG telecon used to discuss compiled science case document.
    • 6/7/06 - Completed science case document sent to SSC co-chairs for SSC distribution.
    • 6/21/06 - AOWG presentation of science case to the SSC.

    July Goal: Preparation of glossy science case for proposal

    Background Materials

  • Committees

    • Solar System

    Galactic

Extragalactic

Technical and Science Instrument(s)

Last Updated: 7/13/06