Spectra and variability of a sample of polar sources

Abstract

The results of 154 daily observations of 33 sources in the declination interval 70°-84.° 5 (J 2000), made in 2009, are reported. Four objects are found to exhibit variations with typical time scales ranging from 8 to 35 days and modulation indices 2.1-5.6%. The spectra of the variable components are obtained. The same sources were observed again after six months, in 2010, for a duration of up to 55 days. The 11.1 GHz flux densities of one third of the sources varied by more than 10% between the two data sets. © 2013 Pleiades Publishing, Ltd.