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arXiv · 1909.01043

Interstellar Scintillation Monitoring of the RadioAstron Blazars

Jun Liu·Thomas P. Krichbaum·Hayley Bignall·Xiang Liu·Alex Kraus·Yuri Y. Kovalev·Kirill V. Sokolovsky·Giuseppe Cimò·J. Anton Zensus
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Abstract

The RadioAstron space radio telescope provides a unique opportunity to study the extreme brightness temperatures ($\mathrm{T_B }$) in AGNs with unprecedented long baselines of up to 28 Earth diameters. Since interstellar scintillation (ISS) may affect the visibilities observed with space VLBI (sVLBI), a complementary ground based flux density monitoring of the RadioAstron targets, which is performed near in time to the VLBI observation, could be beneficial. The combination/comparison with the sVLBI data can help to unravel the relative influence of source intrinsic and ISS induced effects, which in the end may alter the conclusions on the $\mathrm{T_B }$ measurements from sVLBI. Since 2013, a dedicated monitoring program has been ongoing to observe the ISS of RadioAstron AGN targets with a number of radio telescopes. Here we briefly introduce the program and present results from the statistical analysis of the Effelsberg monitoring data. We discuss the possible effects of ISS on $\mathrm{T_B }$ measurements for the RadioAstron target B0529+483 as a case study.

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Jun Liu, Thomas P. Krichbaum, Hayley Bignall, Xiang Liu, Alex Kraus, Yuri Y. Kovalev, Kirill V. Sokolovsky, Giuseppe Cimò, J. Anton Zensus. 2019-09-03. Interstellar Scintillation Monitoring of the RadioAstron Blazars. https://arxiv.org/abs/1909.01043

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