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arXiv · 1503.06593

VLBI observation of the newly discovered z=5.18 quasar SDSS J0131-0321

K. E. Gabanyi·D. Cseh·S. Frey·Z. Paragi·L. I. Gurvits·T. An·Y. K. Zhang
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Abstract

Few high-redshift, radio-loud quasars are known to date. The extremely luminous, radio-bright quasar, SDSS J013127.34-032100.1 was recently discovered at a redshift of $z=5.18$. We observed the source with high resolution very long baseline interferometry (VLBI) at 1.7 GHz with the European VLBI Network (EVN) and found a single compact radio component. We estimated a lower limit to the brightness temperature of the detected radio component, T_B~10^{11} K. Additionaly, when compared to archival radio data, the source showed significant flux density variation. These two findings are indicative of the blazar nature of the source.

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K. E. Gabanyi, D. Cseh, S. Frey, Z. Paragi, L. I. Gurvits, T. An, Y. K. Zhang. 2015-03-23. VLBI observation of the newly discovered z=5.18 quasar SDSS J0131-0321. https://doi.org/10.1093/mnrasl/slv046

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