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Author Colgate, Stirling A. ♦ Li, Hui ♦ Fowler, T. Kenneth ♦ Hooper, E. Bickford ♦ McClenaghan, Joseph ♦ Lin, Zhihong
Source United States Department of Energy Office of Scientific and Technical Information
Content type Text
Language English
Subject Keyword ASTROPHYSICS, COSMOLOGY AND ASTRONOMY ♦ ACCELERATION ♦ ACCRETION DISKS ♦ BLACK HOLES ♦ COMPUTERIZED SIMULATION ♦ COSMIC RADIATION ♦ DENSITY ♦ GALAXIES ♦ GALAXY NUCLEI ♦ JETS ♦ MAGNETIC FIELDS ♦ MAGNETOHYDRODYNAMICS ♦ RELATIVISTIC RANGE ♦ STARS
Abstract This is the second in a series of companion papers showing that when an efficient dynamo can be maintained by accretion disks around supermassive black holes in active galactic nuclei, it can lead to the formation of a powerful, magnetically driven, and mediated helix that could explain both the observed radio jet/lobe structures and ultimately the enormous power inferred from the observed ultrahigh-energy cosmic rays. In the first paper, we showed self-consistently that minimizing viscous dissipation in the disk naturally leads to jets of maximum power with boundary conditions known to yield jets as a low-density, magnetically collimated tower, consistent with observational constraints of wire-like currents at distances far from the black hole. In this paper we show that these magnetic towers remain collimated as they grow in length at nonrelativistic velocities. Differences with relativistic jet models are explained by three-dimensional magnetic structures derived from a detailed examination of stability properties of the tower model, including a broad diffuse pinch with current profiles predicted by a detailed jet solution outside the collimated central column treated as an electric circuit. We justify our model in part by the derived jet dimensions in reasonable agreement with observations. Using these jet properties, we also discuss the implications for relativistic particle acceleration in nonrelativistically moving jets. The appendices justify the low jet densities yielding our results and speculate how to reconcile our nonrelativistic treatment with general relativistic MHD simulations.
ISSN 0004637X
Educational Use Research
Learning Resource Type Article
Publisher Date 2015-11-10
Publisher Place United States
Journal Astrophysical Journal
Volume Number 813
Issue Number 2


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