Challenge: Low frequency foreground hot, confused sky

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Challenge Low frequency foreground hot,
confused sky
0.5 to 5.0 GHz

• HI 21cm signal 10 mK
• Foreground T 100 (?/200 MHz)-2.6 K
• Highly confused 1 source/deg2 with S140 gt 1
  Jy
• Synch. smooth 100MHz vs. 21cm lines 1 MHz

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Chromatic aberration Frequency differencing with
MHz channels doesnt work well due to frequency
dependent far-out sidelobes
142, 174 MHz
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(No Transcript)
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Simulation effects of residual calibration errors
6C source counts gt 1Jy (Smax 200 Jy)
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UVSUB real-time source removal
IMLIN post-processing freq fitting (3rd order)
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Datta 09
0.1
1
For errors constant over 1 day DNR requirement
0.2 calibration errors
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Datta Bowman in prep
300 hours 0.1 calibration errors
UVSUB
IMLIN
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J. Aguirre, D. Jacobs (Penn), C. Carilli (NRAO)

• Focus Reionization (power spec,CSS,abs)
• Very wide field single dipole screen
• Correlator FPGA-based from Berkeley wireless
  lab
• Staged engineering maintain GB test
  installation ? PWA ? PSA

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PAPER Staged Engineering

• Broad band sleeve dipole flaps
• FPGA-based pocket correlator from Berkeley
  wireless lab
• S/W Imaging, calibration, PS analysis AIPY
  Miriad/AIPS gt Python CASA, including
  ionospheric peeling calibration

100MHz
200MHz
Beam response
BEE2 5 FPGAs, 500 Gops/s
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Western Australian deployment in 2008
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PAPER/WA -- 4 Ant, July 2007 RMS 1Jy DNR 1e4
CygA 1e4Jy
Parsons et al. 2009
120MHz
180MHz
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• Paper South Africa
• Karoo site
• 16 elements by Nov 1, 2009
• 32 elements possible by Jan 1

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PGB 16 dipole, 3x24hr

• scale -10 to 10 Jy
• rms 100 mJy
• FWHM 20