ska precursors askap & meerkat - cornell...

ASTRO 7620 Advanced Radio Astronomy Seminar

A m i t V i s h w a s

SKA Precursors: ASKAP & MEERKaT

May 05, 2010

ASTRO 7620 Advanced Radio Astronomy Seminar

Australian SKA Pathfinder (ASKAP)

• Located in Western Australia • One of the most Radio Quiet sites in the World.

• Technology Demonstrator in the Mid-frequency Range

• 700MHz – 1.8GHz

• 30 x 12 mts prime focus Paraboloid Reflectors

• Aeff= ~3400 m2 (~1

20 𝐴𝑟𝑒𝑐𝑖𝑏𝑜)

• Expected Max Baseline of ~ 6 kms

• Working Resolution (10”- 30”)

• Designed to be a fast Survey Telescope • FoV and Survey Speed: Focal Phased Array Feeds

May 05, 2010

ASTRO 7620 Advanced Radio Astronomy Seminar

May 05, 2010

ASTRO 7620 Advanced Radio Astronomy Seminar

Array Configuration - ASKAP

May 05, 2010

36 – 12 mts Antennas Inner Dense Array – 1km radius - Min Separation – 22 mts Outer 6 Antennas - Max Separation 6 kms

ASTRO 7620 Advanced Radio Astronomy Seminar

12m - Parkes Testbed Antenna

May 05, 2010

ASTRO 7620 Advanced Radio Astronomy Seminar

Karoo Array Telescope (MEERKaT)

• Located near the Northern Cape region of South Africa • Population density (0-2/sq.km) - Low man made RFI

• Technology Demonstrator in the Mid-frequency Range • 900MHz – 1.75GHz

• To be extended with 8 - 14.5 GHz & 580 MHz – 2.5 GHz modes

• 80 x 12 mts prime focus Paraboloid Reflectors

• Aeff= ~9000 m2 (~1

8 𝐴𝑟𝑒𝑐𝑖𝑏𝑜)

• Expected Baseline of ~ 8 kms, Extended ~ 60 kms • Working Resolutions 6” – 80”

• Designed to be an extremely sensitive ‘cm’ wavelength Telescope • Large N small D (LNSD)

May 05, 2010

ASTRO 7620 Advanced Radio Astronomy Seminar

May 05, 2010

• XDM : Experimental Development Model • 15 mts Antenna, Technology Testbed (2006-2008)

• KAT 7, now MPA • 7- 12mts Antennas at proposed MeerKaT site (in progress)

ASTRO 7620 Advanced Radio Astronomy Seminar

Array Configuration - MEERKaT

May 05, 2010

80 – 12 mts Antennas Inner Dense Array (70%)– 1km - Min Separation – 20 mts Outer Arms (30%) - Max Baseline – 8 kms 7 Spur Antennas to Baselines of ~ 60 kms

ASTRO 7620 Advanced Radio Astronomy Seminar

KAT – 7 Buildup

May 05, 2010

ASTRO 7620 Advanced Radio Astronomy Seminar

Survey Metrics

• 𝑡 = 2 𝑘 𝑇

𝐴 𝑁 ϵ𝑎 ϵ𝑐

2 1

σ𝑠2𝐵 𝑛𝑝

• Integration time for 𝜎𝑠 sensitivity (Jy)

• 𝑆𝑆𝑠 = 𝐹 𝐵𝑛𝑝𝐴 𝑁 ϵ𝑎 ϵ𝑐 σ𝑠

2 𝑘 𝑇

2, @ 𝜎𝑠 sensitivity, F – FoV

• # sq. deg surveyed per second, 𝜖𝑎, 𝜖𝑐 - Aperture & Correlator Efficiency

• 𝑆𝑆𝑡 = 𝐹 𝐵𝑛𝑝ϵ𝑐 σ𝑡

𝑇

2𝑓2 ϵ𝑠

−2, @ 𝜎𝑡 sensitivity (K), f – filling factor

• Surface brightness temperature SS, 𝜖𝑠- synthesized aperture efficiency

• Large N - Small D – Large FoV (- simultaneous FoVs)

• u-v coverage on the Sky with baselines

May 05, 2010

ASTRO 7620 Advanced Radio Astronomy Seminar

Science Drivers

• Extragalactic HI Science • Evolution of abundance & distribution of HI over different z

• Large Scale HI Survey at intermediate z • For 0.04 ≲ z ≲ 0.2, slightest change in HIMF would result many more

galaxy detections

• Continuum Science • Formation & Evolution of Galaxies, AGNs over time

• Extreme Starburst galaxies over z ~ 6-10 (if they exist)

• Low Luminosity Active Radio galaxies at nearby z (~ 0.5)

• ISM Studies • Better Understanding of Galaxy Evolution through Milky way &

Magellanic Clouds

May 05, 2010

ASTRO 7620 Advanced Radio Astronomy Seminar

Science Drivers

• Pulsar Studies • Larger Pulsar Surveys (30,000 sq deg)

• Computationally limited, ‘ms’ Pulsars missed • Multiple Simultaneous Observations possible

• Exotic High energy Binary systems (Pulsar-Black hole) • Detect Gravitational Waves (?)

• Polarization Studies • Deep survey of polarized emission from Extragalactic Sources • Gather Rotational Measures -> Cosmic Magnetism

• VLBI Science • AGNs with mas jet features, high dynamic range imaging • Radio counterparts of GRBs, other transients

• Large FoV & High Resolution

• Pulsar proper motion & parallax observations

May 05, 2010

ASTRO 7620 Advanced Radio Astronomy Seminar

Timeline

• ASKAP • Currently testing at Parkes Testbed

• Moving to BETA (Boolardy Engineering Test Array) around 2011

• 6 – 12 mts antennas at MRO

• Full ASKAP system up and running by 2013 (Planned)

• MPA & MEERKaT • KAT7/MPA in construction at MeerKaT site.

• 7 – 12 mts antennas (middle of nowhere?)

• Remote operations

• Full MEERKaT system up and running around 2014 (Planned)

May 05, 2010

ASTRO 7620 Advanced Radio Astronomy Seminar

May 05, 2010

2013

2010

Really??

ASTRO 7620 Advanced Radio Astronomy Seminar

1st ASKAP Antenna at MRO

May 05, 2010

ASTRO 7620 Advanced Radio Astronomy Seminar

MPA Buildup (April 2010)

May 05, 2010 Check out www.comparethemeerkat.com

ASTRO 7620 Advanced Radio Astronomy Seminar

References

• ATNF-CSIRO ASKAP Webpage

• http://www.atnf.csiro.au/projects/askap/

• Request for Proposals for MEERKaT

• Heyden, K., Surveying the Sky with MeerKaT, Symposium on Surveying the low frequency sky with LOFAR, Leiden University, NL, March 2010

• Norris, R., Surveying the Sky with ASKAP, Symposium on Surveying the low frequency sky with LOFAR, Leiden University, NL, March 2010

May 05, 2010