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Basic Radiomm Astronomy
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A Crash Course in Radio Astronomy and Interferometry: 1. Basic Radio/mm Astronomy
James Di Francesco
National Research Council of Canada
North American ALMA Regional Center – Victoria
(thanks to S. Dougherty, C. Chandler, D. Wilner & C. Brogan)
Basic Radio Astronomy
Many astronomical sources DO NOT emit as blackbodies!
However….
Brightness temperature (TB) of a source is defined as the temperature of a blackbody with the same surface brightness at a given frequency:
This implies that the flux density
Brightness Temperature
Radio Telescopes
The antenna collects the E-field over the aperture at the focus
The feed horn at the focus adds the fields together, guides signal to the front end
Basic Radio/mm Astronomy
A Crash Course in Radio Astronomy and Interferometry: 1. Basic Radio/mm Astronomy
James Di Francesco
National Research Council of Canada
North American ALMA Regional Center – Victoria
(thanks to S. Dougherty, C. Chandler, D. Wilner & C. Brogan)
Basic Radio Astronomy
Many astronomical sources DO NOT emit as blackbodies!
However….
Brightness temperature (TB) of a source is defined as the temperature of a blackbody with the same surface brightness at a given frequency:
This implies that the flux density
Brightness Temperature
Radio Telescopes
The antenna collects the E-field over the aperture at the focus
The feed horn at the focus adds the fields together, guides signal to the front end
Basic Radio/mm Astronomy
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