Flux of CAS A and CYG A at 320 Mc/sec.
Donald A. Macrae, Ernest R. Seaquist · The Astronomical Journal · 1963
The radio flux at 320 Mc/sec from each of the two strongest sources has been measured at the David Dunlap Observatory of the University of Toronto. Two identical pyramidal horn antennas were used, the gain of each being known from the geometry. A flux measurement consisted of determining the amplitude of an interferometer trace. The radiometer was calibrated with thermal noise sources. The principal uncertainty remaining in the measures lies in our knowledge of the effective apertures of the two horns, and amounts to about 5%. The mean value of the flux from Cas A is 7.83 X 10-23 W m-2 cps-1, and the ratio of the flux of Cyg A to that of Cas A is 0.750.