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Where Can I Find Fluxes for Strong Radio Galaxies?

-- | April 28, 2016

Question: I am trying to calibrate New Horizons radiometry data and need flux of strong radio sources (Cas A, Cyg A, Tau A, and Vir A) at 7182 MHz. Is there a good catalog of this basic information (flux at nearby frequencies plus spectral index) readily available on the web, such as for amateur radio astronomers? My searches so far have turned up lots of specialized survey results and catalogs but not much I can apply to this simple task. — Dick

Answer: You might try the NASA/IPAC Extragalactic Database (NED). As the name implies, this database contains a plethora of information on galaxies, including photometric information. Select the “photometric data point(s) and SED” link within the entry for each galaxy and search for the flux entry corresponding to the frequency you are looking for. For example, Cas A has a flux at 8250 MHz of 620 Jy (with an accuracy of +-4.8%).

Jeff Mangum

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