A New Solution to the Plasma Starved Event Horizon Magnetosphere: Application to the Forked Jet in M87

Abstract

Very Long Baseline Interferometry observations at 86 GHz reveal an almost hollow jet in M87 with a forked morphology. The detailed analysis presented here indicates that the spectral luminosity of the central spine of the jet in M87 is a few percent of that of the surrounding hollow jet $200-400\mu \mathrm{as}$ from the central black hole. Furthermore, recent jet models in indicate that a hollow "tubular" jet can explain a wide range of plausible broadband spectra originating from jetted plasma located within $\sim 30\mu \mathrm{as}$ of the central black hole, including the 230 GHz correlated flux detected by the Event Horizon Telescope. Most importantly, these hollow jets from the inner accretion flow have an intrinsic power capable of energizing the global jet out to kiloparsec scales. Thus motivated, this paper considers new models of the event horizon magnetosphere (EHM) in low luminosity accretion systems. Contrary to some models, the spine is not an invisible powerful jet. It is an intrinsically weak jet. In the new EHM solution, the accreted poloidal magnetic flux is weak and the background photon field is weak. It is shown how this accretion scenario naturally results in the dissipation of the accreted poloidal magnetic flux in the EHM not the accumulation of poloidal flux required for a powerful jet. The new solution indicates less large scale poloidal magnetic flux (and jet power) in the EHM than in the surrounding accretion flow and cannot support significant EHM driven jets.

To appear in Astronomy and Astrophysics. Revision fixes typos found during proofs

References in corpus (13)

• Kinematics of the jet in M87 on scales of 100 -- 1000 Schwarzschild radii
• Magnetically Arrested Disks and Origin of Poynting Jets: Numerical Study
• Dynamics and High Energy Emission of the Flaring HST-1 Knot in the M 87 Jet
• Variable TeV emission as a manifestation of jet formation in M87?
• Magnetization degree at the jet base of M87 derived from the event horizon telescope data: Testing magnetically driven jet paradigm
• Pilot KaVA monitoring on the M87 jet: confirming the inner jet structure and superluminal motions at sub-pc scales
• The effects of resistivity and viscosity on the Kelvin-Helmholtz instability in oscillating coronal loops
• The Spitzer view of FR-I radio galaxies: on the origin of the nuclear mid-infrared continuum
• Relativistic electrons and magnetic field of the M87 jet on ~ten Schwarzschild radii scale
• Evidence of the Dynamics of Relativistic Jet Launching in Quasars
• On the structure of the magnetic field near a black hole in active galactic nuclei
• Dynamic Boundaries of Event Horizon Magnetospheres
• A Jet Source of Event Horizon Telescope Correlated Flux in M87

Cited by in corpus (2)

• Constraints on Black Hole Jet Models Used As Diagnostic Tools of Event Horizon Telescope Observations of M87
• The Details of Limb Brightening Reveal the Structure of the Base of the Jet in M\,87 for the First Time