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arXiv · 2402.19202

VLBI observations of the high-redshift X-ray bright blazar SRGE J170245.3+130104

Yuanqi Liu·Tao An·Shaoguang Guo·Yingkang Zhang·Ailing Wang·Zhijun Xu·Georgii Khorunzhev·Yulia Sotnikova·Timur Mufakharov·Alexander Mikhailov·Marat Mingaliev
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Abstract

Aims. The X-ray luminous and radio-loud AGN SRGE J170245.3+130104 discovered at z $\sim$ 5.5 provides unique chances to probe the SMBH growth and evolution with powerful jets in the early Universe. Methods. We present 1.35 - 5.1 GHz Very Long Baseline Array (VLBA) results on the radio continuum emission and spectrum analysis for this quasar in a low flux density state. Results. This source is unresolved at three frequencies with the total flux densities of 8.35$\pm$0.09 mJy beam-1, 7.47$\pm$0.08 mJy beam-1, and 6.57$\pm$0.02 mJy beam-1 at 1.73 GHz, 2.26 GHz, and 4.87 GHz, respectively. Meanwhile, the brightness temperature is higher than 109 K. Conclusions. Compared with previous radio observations with arcsec-scale resolution, nearly all the radio emission from this source concentrates in the very central milli-arcsecond (mas) scale area. We confirm this source is a bright blazar at z > 5. This young AGN provide us the great chances to understand the first generation of strong jets in the early Universe.

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Yuanqi Liu, Tao An, Shaoguang Guo, Yingkang Zhang, Ailing Wang, Zhijun Xu, Georgii Khorunzhev, Yulia Sotnikova, Timur Mufakharov, Alexander Mikhailov, Marat Mingaliev. 2024-02-29. VLBI observations of the high-redshift X-ray bright blazar SRGE J170245.3+130104. https://doi.org/10.1051/0004-6361%2F202449394

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