Update On The Square Kilometer Array by dandanhuanghuang

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									   Update On The
Square Kilometer Array
   World Space Congress
    October 15, 2002

        Jill Tarter
              What Is The SKA?
• An enormous increase in the capability for
  groundbased radio astronomy
• Increase in sensitivity by a factor of 100 above
  current arrays
• Wide range of science drivers
   – Looking back to the dawn of galaxy formation
   – Mapping the structure of the early universe
   – Searching for evidence of other technological civilizations
• Building to start ~2010
• “Born international”
Stawman Design Goals
                   Timeline
• Annual science/technology workshops began in 1997
• Science With The SKA published in 1999
• 2000 MOU signed by representatives of 27 groups
  from 11 countries
• International SKA Steering Committee formed
• 7 “Whitepaper” end-to-end concepts submitted and
  reviewed – now being revised
• Second round concept papers in 2004
• Concept and site selection 2005-6
• Construction begins in 2010
                                          Radio Telescope Sensitivity
                           5
                               Reber
                           4
                                                                    Jansky 1937 - the beginning
Log Relative Sensitivity




                           3              Dwingeloo


                           2                Jodrell Bank
                                              Parkes
                                                      Bonn
                           1
                                                      WSRT
                                                 Arecibo
                           0                                          AT
                                                                VLA
                                                                             GMRT
                   -1                                                             1hT
                                                                                GBT

                   -2

                                                                                    SKA
                   -3
                    1940           1950   1960    1970       1980     1990   2000   2010

                                                      Date
                                          Radio Telescope Sensitivity
                           5


                                                                                           • Exponential
                               Reber
                           4
Log Relative Sensitivity




                           3              Dwingeloo                                          increase in
                           2                Jodrell Bank                                     sensitivity x 105
                                              Parkes

                           1
                                                      Bonn                                   since 1940 !
                                                      WSRT
                                                 Arecibo
                           0                                          AT
                                                                VLA
                                                                             GMRT
                   -1                                                             1hT
                                                                                GBT

                   -2

                                                                                    SKA
                   -3
                    1940           1950   1960    1970       1980     1990   2000   2010

                                                      Date
The Cosmic Web

Spectra of QSOs show
many Ly-a absorption lines
due to low col. density H

N-body simulations predict
the existence of a cosmic web

Complicated structure of
filaments and sheets of
material

SKA will detect this web
In HI emission!
Normal Galaxies At Large z
                             o
                  SKA’s 1 field-of-view
            for surveys and transient events in 106 galaxies !

                                              SKA 20 cm
15 Mpc at z = 2



                   SKA 6cm
                                   HST



                                                     ALMA
Redshift Surveys
              SKA
       Many beams offer great flexibility

                  SKA Poster




Many targets/users         Interference rejection
Chinese - KARST
FAST
A 500m
Demonstrator
Canadian - LAR
Tether Concept
LAR Prototyping
                 Aerostat
                 Hangar                                    0.8
                                                                                           Balloon and
                                                        t ru


                                                                                           tail inflated
                                                             ss
    Aerostat shown                                              es
    with 10 deg tilt




                                                                                    11.5
                                                                     10.7
concrete
block
columns                  il
                       Ta

                                                Boom                              3.8
                              2.2          Aerostat
              ground level                 launch trailer

                                    14.5                                    1.5
                                                            Dimensions in meters.




                                                                                                           1/3 scale aerostat
                                                                                                           demonstrator funded
           Instrument Platform
                                                                                                 • 4 Focal Plane Array packages
                                                                                                   covering 0.7-1.4 GHz
                                                                                                 • RF Feed design
                                                                                                 • Beam forming
                                                                                                 • Reflector actuators
             US – Large-N/Small-D
                                          84 stations
                                          35-350 km

                                          76 stations
                                          350-3500 km



                                      Inexpensive,
                                      hydroformed
2320 12m antennas within 35 km core   dishes
Based On The ATA
Indian - Preloaded Parabolic Dishes
European – Phased Array Tiles
First Prototype Tile Of 1024
          Elements
Australian – Luneburg Lens
How Does This Work?
Multiple Feeds And Beams
7-arm Spiral Configuration
Australian – Cylindrical Reflector




   RF and Digital Beamforming
Cylindrical Lens Configuration
 The Square Kilometer Array
 Like SETI, the SKA is intrinsically international




                       For SETI,
                     factor of 100
                     in sensitivity
                       another
Decision on           factor of 10
concept and           in distance
site(s) ~ 2005
Expand The Galactic Exploration

      SKA

      ATA

    Phoenix

								
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