what good are low frequencies?

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what good are low frequencies?

• HI, neutral hydrogen, H0, atomic hydrogen
• high redshifts and early times.
• USS, GPS,
• enabling technologies multi-beaming, all-sky
  transients,, the highest energy cosmic rays

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Gigahertz Peak Sources young radio sources ???
FREQ. GHz
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.. ionized
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Cosmic Evolution Indicators
Redshift
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Cosmic Evolution Indicators
Redshift
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3C196-G1 z 0.437 HST image (Ridgway
Stockton)
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Radio spectrum at 988 MHz Westerbork (Briggs,
deBruyn, Vermeulen)
Double Lobed Radio Source
300 km/s
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map emission ?
map absorption ?
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new GMRT
Kanekar Chengalur 988 MHz
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high redshift radio galaxies
TNR J22541857
TNR J1402-1510
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Radio galaxy spectra
No DLA absorption lines
No UV continuum
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Molonglo Telescope SKAMP III

• frequency coverage
• sensitivity
• RFI rejection

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the Molonglo challenges

• broadband line feeds
• 96 station correlator
• Defence HQ 3 km away ?!?!