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

TL;DR

This paper analytically examines whether a distant intermediate-mass black hole could cause the jet precession observed in M87* and concludes it is unlikely based on derived orbital perturbation constraints.

Contribution

It provides a general analytical framework for calculating orbital element changes due to a distant perturber, applied specifically to the M87* system.

Findings

Distant intermediate-mass black holes cannot explain M87* jet precession.

Analytical formulas for orbital perturbations are derived at the Newtonian quadrupolar level.

Parameter space analysis rules out the perturber hypothesis for M87*.

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.