An updated list of radio flux density calibrators

Abstract

We present new flux densities in the range 0.7 cm ≤ λ ≤ 21 cm for the radio sources in the calibrator list of Baars et al. (1977). Most of these sources show significant variability on the time scale of a decade, with the notable exception of 3C286 and 3C295. We use these sources to link our relative measurements to the absolute scale of Baars et al.; for the other sources we present updated spectra. We assess the suitability of the individual sources for use as flux density calibrators