Astron. Astrophys. 344, 51-60 (1999)

VLBI imaging of extremely high redshift quasars at 5 GHz

Z. Paragi ^1,2, S. Frey ¹, L.I. Gurvits ^2,3, K.I. Kellermann ⁴, R.T. Schilizzi ^2,5, R.G. McMahon ⁶, I.M. Hook ⁷ and I.I.K. Pauliny-Toth <sup>8

1</sup> FÖMI Satellite Geodetic Observatory, P.O. Box 546, H-1373 Budapest, Hungary
² Joint Institute for VLBI in Europe, P.O. Box 2, 7990 AA, Dwingeloo, The Netherlands
³ Astro Space Center of P.N. Lebedev Physical Institute, 117924 Moscow, Russia
⁴ National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903-2475, USA
⁵ Leiden Observatory, P.O. Box 9513, 2300 RA, Leiden, The Netherlands
⁶ Institute of Astronomy, Madingley Road, Cambridge CB3 0HA, UK
⁷ European Southern Observatory, D-85748 Garching, Germany
⁸ Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn, Germany

Received 13 November 1998 / Accepted 8 January 1999

Abstract

We present very long baseline interferometry (VLBI) images of ten very high redshift () quasars at 5 GHz. The sources 0004+139, 0830+101, 0906+041, 0938+119 and 1500+045 were observed in September 1992 using a global VLBI array, while 0046+063, 0243+181, 1338+381, 1428+423 and 1557+032 were observed in October 1996 with the European VLBI Network and Hartebeesthoek, South Africa. Most of the sources are resolved and show asymmetric structure. The sample includes 1428+423, the most distant radio loud quasar known to date (). It is barely resolved with an angular resolution of about 2.01.4 mas.

Key words: galaxies: quasars: general radio continuum: galaxies galaxies: active

Send offprint requests to: Z. Paragi, 1st address (paragi@sgo.fomi.hu)

SIMBAD Objects

Contents

• 1. Introduction
• 2. Observations, calibration and data reduction
• 3. Comments on individual sources
• 4. Discussion
• 5. Conclusion
• Acknowledgements
• References

© European Southern Observatory (ESO) 1999

Online publication: March 10, 1999
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