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High-resolution radio imaging of the most distant radio quasar SDSS J0836+0054

S. Frey·Z. Paragi·L. Mosoni·L. I. Gurvits
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Abstract

We observed SDSS J0836+0054, the most distant radio-loud quasar known at present (z=5.774) with the European Very Long Baseline Interferometry (VLBI) Network at the 5 GHz frequency on 2003 November 4. The source is compact at the milli-arcsecond (mas) angular scale with a flux density of 0.34 mJy. The observations with the Very Large Array (VLA) made on the consecutive day support a conclusion that the radio emission from SDSS J0836+0054 is essentially confined within the central 40 pc. Based on our phase-referenced VLBI observation, we obtained the astrometric position of the source accurate to ~2 mas.

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S. Frey, Z. Paragi, L. Mosoni, L. I. Gurvits. 2005-04-20. High-resolution radio imaging of the most distant radio quasar SDSS J0836+0054. https://doi.org/10.1051/0004-6361%3A200500112

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