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arXiv · 2303.00603

Radio jet precession in M81*

S. D. von Fellenberg·M. Janssen·J. Davelaar·M. Zajaček·S. Britzen·H. Falcke·E. Körding·E. Ros
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Abstract

We report four novel position angle measurements of the core region of M81* at 5GHz and 8GHz, which confirm the presence of sinusoidal jet precession of the M81 jet region as suggested by \cite{Marti-Vidal2011}. The model makes three testable predictions on the evolution of the jet precession, which we test in our data with observations in 2017, 2018, and 2019. Our data confirms a precession period of $\sim7~\mathrm{yr}$ on top of a small linear drift. We further show that two 8 GHz observation are consistent with a precession period of $\sim 7~\mathrm{yr}$, but show a different time-lag w.r.t. to the 5 GHz and 1.7 GHz observations. We do not find a periodic modulation of the light curve with the jet precession, and therefore rule out a Doppler nature of the historic 1998-2002 flare. Our observations are consistent with either a binary black hole origin of the precession or the Lense-Thirring effect.

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S. D. von Fellenberg, M. Janssen, J. Davelaar, M. Zajaček, S. Britzen, H. Falcke, E. Körding, E. Ros. 2023-03-01. Radio jet precession in M81*. https://doi.org/10.1051/0004-6361%2F202245506

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