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What are the Radio Filaments Near the Galactic Center?

Published online by Cambridge University Press:  25 May 2016

Mark Morris*
Affiliation:
Department of Physics and Astronomy UCLA, Los Angeles, CA 90024, USA

Abstract

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A population of nonthermally-emitting radio filaments tens of parsecs in length has been observed within a projected distance of ∼130 pc of the Galactic center. More or less perpendicular to the Galactic plane, they appear to define the flux lines of a milligauss magnetic field. The characteristics of the known filaments are summarized. Three fundamental questions raised by these structures are discussed: 1) Do they represent magnetic flux tubes embedded within an ubiquitous, dipole magnetic field permeating the inner Galaxy, but which have been illuminated by some local source of relativistic particles, or are they instead isolated, self-sustaining current paths with an approximately force-free magnetic configuration in pressure equilibrium with the interstellar medium? 2) What is the source of either the magnetic field or the current? and 3) What is the source of the relativistic particles which provide the illuminating synchrotron radiation? We are nearer an answer to the the last of these questions than to the others, although several interesting models have been proposed.

Type
Chapter 3: What is the Nature of the Center of the Galaxy?
Copyright
Copyright © Kluwer 1996 

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