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arXiv · 2508.18881

Can the jet precession of M87$^\ast$ be caused by a distant intermediate-mass black hole?

Abstract

The long-term rates of change of all the Keplerian orbital elements of a two-body system acted upon by a remote massive pointlike object are analytically worked out, to the Newtonian quadrupolar level, without any restriction either on the orbital eccentricity and inclination of the disturbed pair or the position of the distant perturber. The latter is considered fixed during the average over one orbital revolution of the inner binary by means of which its orbital perturbations are calculated. The results are presented in a compact form that facilitates a straightforward application to the case of the supermassive black hole-or megapyknon-M87$^\ast$. In principle, the presence of another distant intermediate-mass black hole may concur to cause the observed jet precession, assumed tightly coupled with the accretion disk. Such a possibility is ruled out by the exclusion plots in the parameter space obtained with the approach presented here.

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Lorenzo Iorio. 2026-01-25. Can the jet precession of M87$^\ast$ be caused by a distant intermediate-mass black hole?. https://doi.org/10.1093/mnras%2Fstag177

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