centre of excellence for all-sky astrophysics mwa project: centre of excellence for all-sky...
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Centre of Excellence for All-sky Astrophysicswww.caastro.orgMWA Project:
Centre of Excellence for All-sky AstrophysicsCentre of Excellence for All-sky Astrophysicswww.caastro.org
MWA Consortium:CurtinU, ANU, UMelbourne, SwinburneU,
USydney, UWestern Australia, UTasmania,
MIT, Harvard-Smithsonian CfA, ASU, UW,
Raman Research Institute, CSIRO
MWA Project:
MWA:
Science Goal: EoR Hydrogen 21cm line @ Z=6-13 80 - 230 MHz … to 320 MHz Statistical Detection throughPower Spectrum: angular scales 4’ to 30’
MWA:
Instrument Strategy:
• Geographic Location
• Large N / Small D
(512/5m)
• Compact Array
• “Real-time System”
Gianni!
Science Goal: EoR Hydrogen 21cm line @ Z=6-13 80 - 230 MHz … to 320 MHz
Location of MWA
Australia’s SKA site
(infrastructure, etc)
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The Shire of Murchison is a large agricultural region in the central part of Western Australia, and is the only shire in Australia without a town.
Population: 114 (2009)Area: 41173 km² (15,897.0 sq mi)
~ Netherlands
Strategy:• less RFI• lower power levels• fewer bits• lower bandwidths• less complexity• lower cost
Small D ~ 5m
Chris Williams (for scale)
Hydra A
115 MHz
50 degbetweennulls
HPBW~ 30 deg
Small D => Large Field of ViewField of View
Virgo A 3C273
Jan 2010
Small D => Large Field of ViewField of View
Aerial Photo of “Small N”“Small N” = 32 Tile Prototype Array:
West-East [m]
Locations of Antenna Tiles in
32T Array
Layout of Large N = 512 Tile Array (128 intermediate)
COMPACT* Densely populated core for Surface Brightness sensitivity (!!!!!)* Ionospheric wobble treated as rubber sheet sky
1.5 km
Strategy:• less complexity• lower cost
Correlator:
• FPGA based “hardware correlator” and fine Filter Bank (10KHz channels)
• Correlate all pairs => 130,816 Interferometer Baselines
• (Prototyping & Testing … baseband recorders, software filter banks, correlators, and beamformers, …)
Hydra A115 MhzJan 2010
Hydra A121 MhzChris WilliamsSep 2010
Pictor A
Parkes Catalog
Pictor A
Parkes Catalog
MWA Sources
32T Image114 MHz
21 57 05.8-69 41 22
UV coverage~10 x 2min
over wide HA range
Centaurus A
Centaurus A
CenA
Left: MWA contours on ACTA+PKS image
Right:MWA 115MHz image
The Sun with MWAComparison with X-ray observations
Solar Radio Bursts 170-200 MHz Oberoi, Matthews, et al
Grid of Radio Spectraacross theface of the Sun
Oberoi, Matthews, et al
Oberoi, Matthews, et alInstantaneous 32T uv-coverage
Ord, Mitchell & Greenhill“2PiP”
baseband recording system
Vela Pulsar
Ord, Mitchell & Greenhill“2PiP”
baseband recording system
MWA EoR Target FieldsChris Williams, MIT
MWA FutureAugust 2011 - lay in the infrastructureDecember 2011 - lay tiles - populate CSIRO facility bldg
(with correlator/RTS hardware)
February 2012 - place receiversJune 2012 - 128T hardware installed - commissioning phase
Contrast between Tb(Moon) and Tb(Sky)
Tb(Sky)
Non-thermal + EoR,etc
Tb(Moon)
Thermal ~B.B.
Experiment:
Tb = Tb(moon) - Tb(sky)
TbTb
BB spectrum: smooth &known
NotSmooth
!?
Recent Data Sets…
LOFAR … several long observations at Full Moon Nov, Dec, Jan, …(?)
MWA… few hours near Full Moon, Sept.
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BenMcKinley,ANU
Moon Field - 83 MHz
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Moon Field - 156 MHz
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Moon Field - 105 MHz Day 1
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Moon Field - 105 MHz Day 2
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80 100 120 140 160 MHz
Tb
= Tb(moon) - Tb(sky)
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