WM Keck Observatory Instrumentat by wulinqing

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									    W. M. Keck Observatory:
Instrumentation, Adaptive Optics
    and Scientific Productivity
            Taft Armandroff
                Director
        W. M. Keck Observatory




                       25 July 2009
                       La Palma, Canary Islands, Spain
          Outline
• Recent Science Highlights
• Current Instrumentation
• Keck Adaptive Optics
• Future Enhancements to Instrumentation
  & Adaptive Optics
• Keck Observatory Scientific Productivity
• Future Strategy

                                       2
Recent Science Highlights




                            3
Mike Liu et al. measure masses of
       brown dwarfs using
 Keck-AO-assisted astrometry




• Angular separations: 0.1-0.2 arcsec
• Periodic images reveal orbits, which give masses
• Compare mass, luminosity and temperature with models   4
Simon/Geha Program to Measure
 Mass-to-Light Ratios of Faintest
    Galaxies in Local Group




• “Missing Dwarfs” Problem from CDM Cosmology
• Spectra from DEIMOS & HIRES give velocity dispersion &
  abundances                                               5
• Most dark matter-dominated galaxies ever found
  Marois, Macintosh et al. Discovery of
Three Planetary Companions to HR 8799




  • Three planets, roughly 10, 10 and 7 times mass of Jupiter
  • First images of an exoplanet system                         6
Current Instrumentation




                          7
                                                                                             Wavelength
       Name             Acronym   Tel. & Pos.                 Type / FOV                       range                 Detector
                                                                                                          Red - mosaic of two 2048 x 4096
Low Resolution                                  Imager 6' x 8'
                                  Keck I                                                                  LBNL CCDs
Imager /               LRIS                     Spectrograph: Long slit; Multi-slit (≤    310 - 1000 nm
                                  Cass.                                                                   Blue - mosaic of two 2048 x
Spectrograph                                    30) R = 500 – 3,000
                                                                                                          4096 E2V CCDs

                                                                                                          Mosaic of three 2048 x 4096
High Resolution                   Keck I        Echelle Spectrograph:
                       HIRES      RNAS          R = 30,000 – 80,000
                                                                                          350 - 1000 nm   MIT/LL MBE CCDs (2 blue, 1
Echelle Spectrometer                                                                                      red)

Near Infrared                     Keck I        Imager 38" x 38"                                          Hughes/SBRC 256 x 256 InSb
                       NIRC                                                               0.8 – 5.5 µm
Camera                            Cass.         Spectrograph: R = 164                                     detector

                                                                                                          Rockwell HgCdTe 256 x 256
                                  Keck II
Near Infrared                                   Imager 46" x 46"                          0.95 - 2.5 µm   and
                       NIRSPEC    LNAS AO
                                                Spectrograph: R = 2,000 & 25,000          0.95 - 5.5 µm   Aladdin-III 1024 x 1024 InSb
Spectrometer                      RNAS
                                                                                                          (Raytheon)

                                                Imager 2' x 8'
Echellette
                                  Keck II       Spectrograph:                                             2048 x 4096, 15 µm pixel
Spectrograph and       ESI        Cass.         Echellette R up to 32,000
                                                                                          390 - 1100 nm
                                                                                                          MIT/LL CCD
Imager                                          Low dispersn R = 6,000 to 1,000

                                                Imager:
                                                10" x 10" (narrow camera)
Near Infrared                     Keck II                                                                 Aladdin-III 1024 x 1024 InSb
                       NIRC2      LNAS AO
                                                20" x 20" (medium camera)                 0.9 - 5.3 µm
                                                                                                          (Raytheon)
Camera 2                                        40" x 40" (wide camera)
                                                Spectrograph: R = 5,000

                                                Imager 17' x 5'
Deep Extragalactic
                                  Keck II       Spectrograph: Multi-slit (up to 130       400 - 1050 nm   Mosaic of eight 2048 x 4096, 15
Imaging and Multi-     DEIMOS     RNAS          slitlets with 1.5" gaps)                  410 - 1100 nm   µm pixel MIT/LL CCD
Object Spectrograph                             R = 6,000

                                                Imager 0.02“ pixel scale 20”x20” field
                                                                                                          Imager:
OH Suppressing                                  IFU sampling:0.02" to 0.1" plate scales
                                  Keck II       Broadband 16x64 elements                                  Hawaii-I 1024x1024 HgCdTe
InfraRed Imaging       OSIRIS     LNAS AO
                                                                                          0.95 - 2.5 µm
                                                                                                          Spectrograph:         8
                                                Narrowband 48x64 elements
Spectrograph                                                                                              Hawaii-II 2048x2048 HgCdTe
                                                Spectrograph: R = 3,900
             LRIS Red Channel
             Detector Upgrade
• Upgrade to a mosaic of two
  2K x 4K high resistivity, thick
  substrate detectors (LBNL)
• Significant QE improvement
• No fringing
• Typically 25% more spectral
  coverage
• New dewar, focus mechanism &
  red channel electronics
• First light 6 June 2009
                                    9
Keck Adaptive Optics




                       10
                       LGS AO Science
                             Galactic Center
      KBO’s




                                               Bipolar
                                               Jet




                                                         11
Methane brown dwarfs
                     0
                                                        1
            Jan-99
                            K2 NGS
            Jan-00
            Jan-01       K2 NIRSPAO

            Jan-02        K2 NIRC2
                         K1&2 NGS Interferometer
            Jan-03
            Jan-04
                             K2 LGS
            Jan-05
                          K2 OSIRIS
            Jan-06
            Jan-07         K1&2 WFC Upgrade




     Date
            Jan-08
            Jan-09
            Jan-10         K1 LGS + OSIRIS +
                              Interferometer
            Jan-11
                                                   Future




                           K2 Center Launch
            Jan-12
            Jan-13
                                                            Keck AO First TAC-allocated Science Milestones




            Jan-14
            Jan-15          K2 NGAO + Camera
                                                                                                             Keck AO Science Capabilities




12
     Future Enhancements to
Instrumentation & Adaptive Optics




                               13
                           MOSFIRE
Multi-Object Spectrometer For InfraRed Exploration

• Near-IR Multi-Object Imaging
  Spectrometer
   – 0.97 to 2.45 m
• At Cass focus of Keck I, MOSFIRE
  will provide:
   – R = 3,270 for a slit width of 0.7"
   – 46 slits over 6.1' x 3' FOV using a remotely
     configurable slit mask unit
   – Imaging FOV 6.14' diameter with 0.18" pixels
• Cold testing underway
• First light in June 2010
                                                    14
               Keck I LGS AO
• LGS AO for Keck I telescope (2010)
  – Higher performance than Keck II LGS AO
     • Higher power laser
     • Center launch telescope
  – OSIRIS at fixed location with one less reflection
  – LGS AO for Keck Interferometer & redundancy of key
    science capability




                                                         15
              ASTRA overview
Based on NASA investments in Keck Interferometer
Based on K2 and K1 LGS AO capabilities
July 2006 ~ July 2010

                                                            Young Stellar Objects
                           1                                Chemical Composition at R~1800
                                      Self
                                Phase Referencing

                                       K<8 limit
                                       R~1800

                                          2
                                                 Dual Field               Active Galactic Nuclei
                                              Phase Referencing           Chemical Composition
                                                                          Increased Sample
                                          K<8.5 reference
                                          K<15 science
                           3
                                    Astrometry
                                                                                               Galactic Center
                               30μ˝ for                                                        Stellar Population
                               30˝ separation                                                  BH mass
                                                                                               and GR effects


Three new operating modes                                            Exoplanets
                                                                     Reflex Motion of
Four science cases                                                   Multiple Planet Systems
                                                                                                        16
NGAO - Next Generation AO
                       Key Science Goals
  Understanding the Formation and Evolution of Today’s Galaxies
        Measuring Dark Matter in our Galaxy and Beyond
  Testing the Theory of General Relativity in the Galactic Center
 Understanding the Formation of Planetary Systems around Nearby
                             Stars

            Exploring the Origins of Our Solar System
                 Key New Science Capabilities
     Near Diffraction-Limited in Near-IR (K-Strehl ~80%)
       AO correction at Red Wavelengths (0.65-1.0 m)
                  Increased Sky Coverage
    Improved Angular Resolution, Sensitivity and Contrast
      Improved Photometric and Astrometric Accuracy
          Imaging and Integral Field Spectroscopy
                                                                    17
How is NGAO different from
      Keck AO today?




                             18
NGAO System
 Architecture

           Key Features:
           1. Fixed narrow field laser tomography
           2. AO corrected NIR TT sensors
           3. Cooled AO enclosure smaller
           4. Cascaded relay
           5. Combined imager/IFU instrument




                                                    19
      NGAO in the world of 8-10 m telescopes:
      Uniqueness is high spatial resolution, shorter ’s,
                      AO-fed NIR IFS
                  Table 1. Next-Ge ne ration AO Syste ms Under Deve lopment for 8 - 10 meter Telescopes

                                           Next-Generation AO Systems
          Type         Telescope    GS                                            Capabilities             Date s
                                             for 8 to 10 m telescopes

                                                                         Good Strehl, 188-act curvature,
       High-contrast    Subaru     N/LGS Coronagraphic Imager Hi(CIAO)                                     2008
                                                                                   4W laser

       High-contrast     VLT       NGS      Sphere (VLT-Planet Finder)             High Strehl             2010


       High-contrast Gemini-S      NGS      Gemini Planet Imager (GPI)          Very high Strehl           2010


        Wide-field     Gemini-S    5 LGS             MCAO                            2Õ FOV                2009


        Wide-field      Gemini     4 LGS             GLAO                  Feasibility Study Completed       ?

                                            HAWK-I (near IR imager) +     7.5' FOV, AO seeing reducer,
        Wide-field       VLT       4 LGS                                                                   2012
                                               GRAAL GLAO                        2 x EE in 0.1''

                                              MUSE (24 vis. IFUs) +
        Wide-field       VLT       4 LGS                                 1' FOV; 2 x EE in 0.2" at 750nm   2012
                                               GALACSI GLAO

                                              MUSE (24 vis. IFUs) +      7.5Ó FOV, 10% Strehl @ 750 nm
       Narrow-field      VLT       4 LGS                                                                   2012
                                               GALACSI GLAO               in best seeing, low sky coverage


• Most 8-10 m telescopes plan either high contrast or wide field AO
                                                                                                                    20
 Keck Observatory
Scientific Productivity




                          21
Number of Publications per Year




 Number of refereed publications increasing over time
                                                        22
Papers per Telescope




                       23
                                            Keck AO Science Product
    217 refereed science papers (thru May/09)                                                                                          25




                                                                                                     Number of Refereed Publications
                                                                                                                                               Solar System     29%
                              30                                                                                                       20      Galactic         52%
                                           Interferometer
                                                            10%                                                                                Extra-galactic   19%
Number of Papers (per year)




                              25           LGS              26%                                                                        15
                              20
                                           NGS              64%
                                                                                                                                       10
                              15

                              10                                                                                                        5

                              5
                                                                                                                                        0
                              0
                                                                                                                                        2000 2001 2002 2003 2004 2005 2006 2007 2008
                              2000        2001    2002   2003     2004   2005   2006   2007   2008                                                                Year
                                                                  Year

                                                                               Number of
                                   Area                   Sub-Topic             Papers
                                                 Brown dwarfs & low mass stars    15
                                                        Galactic Center           10
                                                       Compact objects             2
                              Galactic                  Star formation             1
                                                     High redshift galaxies       11
                                                     Gravitational lensing         5
                               Extra-                 Stellar populations          3
                              galactic                   Supernovae                5
                               Solar                      Kuiper Belt              4
                                                                                                                                                                            24
                              System                       Asteroids               1
LGS-AO Refereed Science Papers




    M. Liu




       Compiled by Michael Liu (U. Hawaii)   25
Future Strategy




                  26
     Scientific Strategic Plan
             Mission Statement

• High angular resolution astrophysics
• Faint object, high-precision & highly-
  multiplexed spectroscopy from UV through K
• Highly efficient operations
• Flexibility to exploit emerging opportunities
• Training the future leaders of the field


                                              27
        Strategies for Keck in
           the ELT Era (1)
• Organizational
   – Nimbleness re new opportunities
   – Preserve strong relationship with our user community
• Observing programs
   – More large programs
   – Programs that study sample of objects with Keck, then
     ELT follow-up of the most interesting objects
   – Greater exploitation of time domain
   – Exploit new wide-field imaging surveys
      • Imbalance between resources dedicated to new imaging surveys
        and follow-up capability
                                                                       28
       Strategies for Keck in
          the ELT Era (2)
• Instrumentation & adaptive optics
  – Must continue to invest in compelling new
    instrumentation & adaptive optics systems
  – Higher-risk, high-reward instruments & AO
     • ELTs do not have appetite for risk in instrumentation
     • 8-10 m telescopes will be proving ground for new,
       innovative instrument concepts
     • More specialized instruments than might be selected as
       1st generation ELT instruments
  – Interferometry
                                                            29
Welcome GTC!

								
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