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arXiv · 2310.08902

Detection of a ~ 0.1c radio knot in M81* associated with a moderate X-ray flare

Xuezheng Wang·Wu Jiang·Zhiqiang Shen·Zhen Yan·Ya-Ping Li·Ivan Martí-Vidal·Roman Gold
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Abstract

Through very long baseline interferometry observations of one of the closest low-luminosity active galactic nuclei M81* at multifrequencies of 8.8, 22 and 44GHz, a bright discrete knot with an unusual low apparent speed $\sim$0.1c was detected. Combining with the contemporary monitoring of X-rays data at 2-10keV, it indicates that a moderate X-ray flare happened when the knot launched from the core region. Three possible origins of the knot are proposed to explain our observational results. They are an episodic jet ejection, a low-speed shock wave, and a possible secondary black hole in a binary system, respectively. Future intensive multiwavelength monitoring can help to understand the discrete knot as well as the central black hole better.

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Xuezheng Wang, Wu Jiang, Zhiqiang Shen, Zhen Yan, Ya-Ping Li, Ivan Martí-Vidal, Roman Gold. 2023-10-13. Detection of a ~ 0.1c radio knot in M81* associated with a moderate X-ray flare. https://arxiv.org/abs/2310.08902

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