Evidence of the Dynamics of Relativistic Jet Launching in Quasars

TL;DR

This paper presents evidence supporting a model where magnetic flux tubes in the innermost accretion flow of quasars lead to magnetically arrested accretion, explaining the EUV deficit and jet power regulation.

Contribution

It provides observational support for the magnetically arrested accretion (MAA) model linking EUV deficits to magnetic flux distribution and jet dynamics in quasars.

Findings

EUV deficit correlates with magnetic flux tube presence.

Jet strength is regulated by accretion flow ram pressure.

Energy removal from accretion flow is proportional to the EUV gas displacement.

Abstract

Hubble Space Telescope (HST) spectra of the extreme ultraviolet (EUV), the optically thick emission from the innermost accretion flow onto the central supermassive black hole, indicate that RLQs tend to be EUV weak compared to the radio quiet quasars (RQQs); yet the remainder of the optically thick thermal continuum is indistinguishable. The deficit of EUV emission in RLQs has a straightforward interpretation as a missing or a suppressed innermost region of local energy dissipation in the accretion flow. This article is an examination of the evidence for a distribution of magnetic flux tubes in the innermost accretion flow that results in magnetically arrested accretion (MAA) and creates the EUV deficit. These same flux tubes and possibly the interior magnetic flux that they encircle are the source of the jet power as well. In the MAA scenario, islands of large scale magnetic vertical flux perforate the innermost accretion flow of RLQs. The first prediction of the theory that is supported by the HST data is that the strength of the (large scale poloidal magnetic fields) jets in the MAA region is regulated by the ram pressure of the accretion flow in the quasar environment. The second prediction that is supported by the HST data is that the rotating magnetic islands remove energy from the accretion flow as a Poynting flux dominated jet in proportion to the square of the fraction of the EUV emitting gas that is displaced by these islands.