Comparison of ejection events in the jet and accretion disc outflows in 3C 111

TL;DR

This study compares accretion disc outflows and jet ejections in galaxy 3C 111, revealing their coexistence, pressure equilibrium, and potential feedback effects, while exploring their connection to flux variations and jet ejection cycles.

Contribution

It provides the first detailed comparison of UFOs and jet parameters in 3C 111, highlighting their possible physical link and impact on the environment.

Findings

UFOs and jets coexist on sub-pc scales.

UFOs are more massive but less kinetic power than jets.

UFOs are detected during flux increases and possibly linked to X-ray dips.

Abstract

We present a comparison of the parameters of accretion disc outflows and the jet of the broad-line radio galaxy 3C 111 on sub-pc scales. We make use of published X-ray observations of ultra-fast outflows (UFOs) and new 43GHz VLBA images to track the jet knots ejection. We find that the superluminal jet coexists with the mildly relativistic outflows on sub-pc scales, possibly indicating a transverse stratification of a global flow. The two are roughly in pressure equilibrium, with the UFOs potentially providing additional support for the initial jet collimation. The UFOs are much more massive than the jet, but their kinetic power is probably about an order of magnitude lower, at least for the observations considered here. However, their momentum flux is equivalent and both of them are powerful enough to exert a concurrent feedback impact on the surrounding environment. A link between these components is naturally predicted in the context of MHD models for jet/outflow formation. However, given the high radiation throughput of AGNs, radiation pressure should also be taken into account. From the comparison with the long-term 2-10keV RXTE light curve we find that the UFOs are preferentially detected during periods of increasing flux. We also find the possibility to place the UFOs within the known X-ray dips-jet ejection cycles, which has been shown to be a strong proof of the disc-jet connection, in analogue with stellar-mass black holes. However, given the limited number of observations presently available, these relations are only tentative and additional spectral monitoring is needed to test them conclusively.