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					                                    Keck Adaptive Optics Note 271
             AOWG Strategic Planning: How has the Landscape changed?
                                  P. Wizinowich for the Keck AO Team
                                          September 14, 2004

Table of Contents
        1. Introduction
        2. Progress on the Nov/02 AOWG Strategic Plan
        3. Keck AO team Staffing
        4. Current FY05 and 06 Plans
        5. Potential Funding Sources and Collaborations
        6. Current NGS and LGS Performance
        Appendix 1. AO Community Overview

1. Introduction

The purpose of this document is to support the Sept/04 AOWG strategic planning meeting by briefly
summarizing what has changed at Keck and within the AO community since the Nov/02 AOWG strategic
planning meeting.

2. Progress on the Nov/02 AOWG strategic plan

The following figure was generated at the Nov/02 strategic planning meeting.




                                                    1
The current status of the items identified in the above diagram, is as follows:

1.   Laser guide star:
      Laser operations have been significantly improved.
      Laser reliability due to amplifier burns is a serious issue.

2.   LGS AO:
      The system is beginning to produce impressive science.
      We have demonstrated good progress on milestones over the past couple of years.
      Shared-risk science nights scheduled for 04B and 05A.
      A significant amount of engineering and optimization remains.

3.   OSIRIS.
      OSIRIS is scheduled for its first light in early Dec.

4.   NGS AO optimization:
      The performance has been significantly improved.
      The operability and reliability has been significantly improved.
      ~50 refereed science papers versus ~20 in 11/02.
      Currently working on the release of the 1”/pixel wavefront sensor plate scale for improved Strehl.
      Telescope optics: Full-time optics engineer hired in mid-03 to work on understanding and
        improving the telescope optical performance.

5.   New wavefront controller:
      The Keck Foundation provided $2M in Jan/04.
      Work has started at Keck and JPL on this effort.
      A conceptual design review will occur within a month.

6.   KPAO:
      Top-level requirements & constraints document produced.
      The Observatory has provided 1.5 ftes in FY05 to start on a conceptual design.
      Full-time lead identified starting in FY05 (for 2 years).
      CfAO/TMT funded postdoc position being advertised.

7.   ExAO
      Not currently being pursued for Keck.
      An extreme AO system was identified at Gemini's Aspen retreat as one of the 3 top-priorities for
        new instruments. Two ExAO conceptual designs have been funded (XAOPI and a Steward
        Observatory design).

Subsequent to the strategic planning meeting, the AOWG also recommended that we proceed with a laser
for Keck I. The status of this item is as follows:

8.   New laser:
      The NSF has provided $2.5M for a facility-class commercial laser for Keck.
      Ready to go out for RFP this fall (all documentation is ready).
      Technical progress on multiple lasers: The SOR SFG laser has demonstrated 20W, and a 50W
        version is nearing completion. The Altair SFG laser has demonstrated 8W and is to be delivered
        in Dec. Good progress on the LLNL fiber laser.
      Unclear that we can afford a commercial vendor. A joint Gemini/Keck fabrication of lasers is
        being discussed.




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3. Keck AO Team Staffing

The Keck AO team has grown significantly in experience and numbers over the past two years.
     New members:
           o Robert Lafon. Laser optics engineer. Started in 8/02.
           o Erik Johansson. Software engineer. Started in 2/03.
           o Antonin Bouchez. CfAO funded postdoc working on LGS AO. Started in 9/03.
           o Marcos van Dam. Started a 2 year position at Keck in Aug. (had been a postdoc).
           o Chris Neyman. KPAO lead starting in 10/04.
     Advertised positions:
           o AO system engineer. Open position (replaces Adam Contos' position).
           o KPAO postdoc. New position.
     AO member who started before Aug/02: Jason Chin, Scott Hartman, David Le Mignant, Paul
        Stomski, Doug Summers, Peter Wizinowich.

4. Current FY05 and 06 Plans

The Observatory has already developed its plan for FY05 and has a tentative plan for FY06. The FY05
staffing and procurements plan is as follows:

       K2 LGS AO.                5.2 FTEs & $50k.          Including CfAO-funded postdoc.
       New wavefront controller. 3.0 FTEs & $580k.         In collaboration with JPL.
       KPAO studies.             1.5 FTEs & $10k.          Plus CfAO/TMT-funded postdoc.
       NSF laser development. 0.2 FTEs & $55k.             Plus NSF funding to procure laser.
       K2 NGS AO operations. 1.5 FTEs & $20k.
       Research time.            0.8 FTEs
                         Total = 12.2 FTEs & $715k.

5. Potential Funding Sources and Collaborations

   Keck Foundation
     Our first funding request to the Keck Foundation, since the funding of the two telescopes and
        Keck II AO system, successfully obtained funding for our new wavefront controller system.
     The potential for future funding is uncertain.
   TMT
     Discussions were recently initiated on potential AO collaborative efforts with TMT during a Keck
        site visit made by Sanders & Nelson. Some collaborations already exist, including the KPAO
        postdoc. Further discussions are planned to occur in September.
   CfAO
     The CfAO has funded two of our postdocs (Marcos van Dam and Antonin Bouchez) and has
        committed to funding half of the KPAO postdoc in FY05. We have also collaborated with other
        CfAO postdocs such as Matthias Schoeck, Frank Marchis and Paul Calas.
   AODP
     During the 03 AODP funding round a Keck-based proposal to produce new CCDs for AO was
        successful.
     A letter of intent for the 04 round has been submitted entitled "Optimal measurement & correction
        of low order WF errors in LGS AO systems."
   Future funding.
     The CARA Board has agreed to an active approach to seeking external funds to support new
        instrumentation. UCLA will lead the Keck AO fundraising effort.




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6. Current NGS & LGS Performance

The current Strehl and FWHM performance of the Keck AO systems is shown in the following figures.


                                            K-band Strehl Ratio versus R-magnitude
                                  0.6                                             LGS 7/26/04 r0=17-31cm
                                                                                  LGS 7/27/04 r0=14-17cm
                                  0.5                                             LGS 9/01/04 r0=22-25cm
                                                                                  NGS r0~20cm
                   Strehl Ratio




                                  0.4

                                  0.3

                                  0.2

                                  0.1

                                   0
                                        6       8        10      12          14        16      18      20
                                                               R-magnitude


                                            K-band FWHM versus NGS R-magnitude
                                120
                                                    LGS 7/26/04 r0=17-31cm
                                110
          FWHM (milli-arcsec)




                                                    LGS 7/27/04 r0=14-17cm
                                100                 LGS 9/01/04 r0=22-25cm
                                  90                NGS r0~20cm

                                  80
                                  70
                                  60
                                  50
                                  40
                                        6      8        10      12      14            16      18      20
                                                              R-magnitude

The 5-sigma NIRC2 detection limits after 3600s on-source are currently L'=19.1 (Strehl=0.75) and
Ms=15.7 (Strehl=0.85). For comparison, the theoretical limiting magnitude of the Keck 1 NIRC
instrument, if it were fed by a zero-emissivity AO system and its platescale was adjusted appropriately,
would be L'=20.9 and Ms=18.0.




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                            Appendix 1. AO Community Overview
                                        Compiled by Chris Neyman
                                                 9/13/04

A brief summary of the adaptive optics systems that are planned, being constructed and starting scientific
observation is provided. These systems are grouped in the following areas of performance:

    1.   NGS AO: Single natural start adaptive optic systems.
    2.   LGS AO: Single laser guide star adaptive optic systems.
    3.   MCAO: Multi conjugate AO system. These systems attempt to correct a field of view larger than
         the isoplanatic angle by a using multiple deformable mirrors, multiple natural and/or laser guide
         stars and multiple wavefront sensors.
    4.   Spectroscopy: Spectrographs especially designed to take advantage of the smaller point spread
         function of an AO corrected telescope.
    5.   XAO: extreme AO systems that attempt to achieve very high Strehl ratio compensation. Mostly
         for detecting planets close to bright stars.
    6.   GLAO: Ground layer AO. “Seeing improvement” systems characterized by wide field of view
         (many arc minutes) and FWHM of 0.1-0.3 arc seconds.
    7.   Interferometry: limited to stellar interferometry with AO corrected large telescopes.
    8.    MOAO: Multi object AO. This is a catch all category that included cone effect only AO systems
         and systems that have multiple AO correcting mirrors that each correct a separate object in the
         telescopes field of view.
    9.    TMT/ELT/GMT: AO for the upcoming large telescopes in the 30-100 m class.

A list of systems under each of the above categories, along with some details, is provided in the following
sections. The expected dates for specific systems are shown in the timeline at the end of this Appendix.

Natural Guide Star AO.
     NACO (NAOS+CONICA): A 1-5 micron Infrared Imager (CONICA) fed by high order Shack-
        Hartmann AO system on VLT unit telescope 4. (ESO)
     ALTAIR: Higher order Shack-Hartmann AO system on the GEMINI north telescope.
     LBT: large binocular telescope features adaptive secondary and pyramid wavefront sensor.
     Subaru: Subaru will upgrade from 33 actuator curvature system to 188 actuator curvature sensor
        system.
     GTC: Gran Telescopio Canarias plans to build an AO system very similar to Keck AO system on
        its Keck clone 10.4 m telescope.

Laser Guide Star
     NACO-LGS: laser guide star for ESO NAOS system
     WMKO: Keck Observatory will support LGS-AO science observation.
     Subaru: 188 actuator curvature AO system will be equipped with laser guide star.

MCAO
   MGSU: multiple guide star unit at Palomar observatory is a test bed for MCAO natural guide star
     testing, to be followed by LGS MCAO testing.
   MAD: Natural guide start MCAO demonstrator/test bed at VLT (ESO).

Spectroscopy
     OSIRIS Near IR integral field spectrograph to be coupled to Keck II LGS AO system.
     SIFFI/SINFONI Near IR integral field spectrograph, coupled to dedicated 60 actuator curvature
        AO system.
     CRIRES-AO Nasmyth curvature AO system to feed cryogenic IR echelle spectrograph.

Extreme AO



                                                     5
       Lyot Project. Coronagraph installed on the AEOS 3.5m telescope behind its AO system.
       NICI: Gemini South telescope coronagraph with dedicated curvature sensor AO system.
       Gemini has commissioned two ExAO conceptual designs based on
            o LLNL-based proposal. XAOPI.
            o Steward Observatory-based proposal.

Ground layer AO
    HAWK-I Near IR imager, fed from adaptive secondary mirror with multi LGS tomographic
        wavefront sensing.
    MUSE Visible integral field spectrograph, fed from adaptive secondary mirror with multi LGS
        tomographic wavefront sensing.
    Both MUSE and HAWK-I use facility adaptive secondary for seeing improvement.

MOAO
   KPAO Keck Precision Adaptive Optics system it corrects for Cone Effect only i.e. use only 1
     deformable mirror but several wavefront sensors and LGS.
   MUSE (narrow FOV mode), Cone effect only narrow field of view mode of ESO ground layer AO
     system.
   FALCON




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