Open AccessJournal Article
Flicker of Extragalactic Radio Sources at Two Frequencies
TLDR
In this paper, dual-frequency observations of flat and steep-spectrum extragalactic radio sources made at Arecibo Observatory over a 20-day period are analyzed.Abstract:
Dual-frequency observations of flat and steep-spectrum extragalactic radio sources made at Arecibo Observatory over a 20-day period are analyzed. As first reported by Heeschen (1982, 1984), flat-spectrum sources generally have larger intensity variations than steep-spectrum ones. A structure function analysis demonstrates a qualitative difference in the time series of the sources. The case against interstellar scintillation is examined, including a review of applicable scintillation theory. Relativistic source motion is treated as a solution to the brightness-temperature problems which arise if the variations are assumed intrinsic to the sources. 16 references.read more
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