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Detection of the VLBI-scale Counter Jet in NGC 6251

H. Sudou·Y. Taniguchi·Y. Ohyama·S. Kameno·S. Sawada-Satoh·M. Inoue·O. Kaburaki·S. Sasao
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Abstract

Mapping the central 5 pc region of the nearby radio galaxy NGC 6251 with a 0.2 pc resolution using VLBI at two radio frequencies, 5 GHz and 15 GHz, we have found the sub-pc-scale counter jet for the first time in this radio galaxy. This discovery allows us to investigate the jet acceleration based on the relativistic beaming model (Ghisellini et al. 1993).

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H. Sudou, Y. Taniguchi, Y. Ohyama, S. Kameno, S. Sawada-Satoh, M. Inoue, O. Kaburaki, S. Sasao. 2000-04-12. Detection of the VLBI-scale Counter Jet in NGC 6251. https://arxiv.org/abs/astro-ph/0004139

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