Coffee talks
Friday 08/02/2019 @ 11:30, Sala riunioni quarto piano
Evgeniya Kravchenko (INAF-IRA), "Observations of the blazar S5 0716+71 with RadioAstron"
The blazar S5 0716+71 (0716+714) is well famous due to its extreme variability throughout the whole electromagnetic spectrum, with time scales that range from hours to months, including intra-day variability (IDV). It is considered as one of the best candidates for having an intrinsic origin of the observed IDV, rather than being produced by scintillation of the ionized interstellar medium. Space VLBI observations of 0716+714, performed with the VSOP, revealed IDV in both, total and linearly polarized flux densities, originated within a source size of a few microarcseconds, well below the angular resolution provided by VSOP and ground VLBI arrays. In this talk I will present the results of the observations of the blazar made with RadioAstron Space VLBI mission within its two Key Science Programs. It has been observed at 1.7, 4.8 and 22 GHz almost 100 times on the projected baselines up to 25.5 Earth diameters, equivalent to 324~900~km. We build full-polarimetric image of the blazar with unprecedented angular resolution of 24 microarcseconds, highest for the source to date. This enabled us to analyse its detailed structure and study its other peculiar properties.