Effelsberg Monitoring of a Sample of RadioAstron Blazars
نویسندگان
چکیده
The launch of the RadioAstron space radio telescope provides a unique opportunity to 1 study the extreme high brightness temperature of Active Galactic Nuclei (AGNs) with unprecedented 2 long baselines of up to 28 Earth diameters. A coordinated ground-based flux density monitoring of 3 RadioAstron targets is essential to determine the effect of interstellar scintillation (ISS) on the Space 4 Very Long Baseline Interferometry (SVLBI) visibilities. Moreover, a combination/comparison of 5 scintillation with SVLBI observations is expected to reveal the relative influence of source brightness 6 temperature, compactness, and properties of the interstellar medium on the observed variability at 7 centimeter wavelengths. In 2014 we started a RadioAstron target triggered flux monitoring with 8 the Effelsberg 100-m radio telescope in support of this SVLBI mission. A total of 112 targets were 9 observed during the five-session monitoring performed so far. In this paper we present a statistical 10 study on the short-term flux density variability of the sample, which is focused on the variability 11 characteristics and derived physical properties of the observed sources. 12
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