Unbound geodesics from the ergosphere and the M87 jet profile

TL;DR

This paper models unbound geodesics originating from the ergosphere of a maximally spinning black hole in M87, aligning theoretical predictions with high-resolution observations of the jet's origin and structure.

Contribution

It introduces a novel analysis of unbound geodesics from the ergosphere of a Kerr black hole to explain the M87 jet profile, assuming maximal ergospheric volume.

Findings

Unbound geodesics can explain the jet's observed profile.

Jet origin is consistent with inside the innermost stable circular orbit.

Maximal black hole spin aligns with observed jet features.

Abstract

Assuming that the spin $a$ of the black hole, presumably located at the core of the active galactic nuclei Messier 87 (M87), takes the value which maximises the ergospheric volume of the Kerr spacetime, we find results compatible with the recent observations obtained by high resolution interferometry on the origin of the jet, which would be located inside the innermost stable circular orbit diameter. Moreover, we find a flow of unbound geodesics issued from the ergoregion able to frame the best fits at large scale recently obtained for describing the observed profile of the relativistic jet launched from this central engine.