Published May 2001 | Version v1
Journal article

The origin of the magnetic fields of the universe: The plasma astrophysics of the free energy of the universe

  • 1. P.N. Lebedev Physical Institute, Leninsky Prospect 53, Moscow 11792 (Russian Federation)
  • 2. Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, Arizona 85721 (United States)
  • 3. Theoretical Astrophysics, T6, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

Description

The interpretation of Faraday rotation measure maps of active galactic nuclei (AGNs) within galaxy clusters has revealed ordered or coherent regions, Lmag∼50-100 kpc (∼3x1023 cm), that are populated with large, ∼30 μG magnetic fields. The magnetic energy of these coherent regions is Lmag3(B2/8π)∼1059-60 ergs, and the total magnetic energy over the whole cluster (∼1 Mpc across) is expected to be even larger. Understanding the origin and role of these magnetic fields is a major challenge to plasma astrophysics. A sequence of physical processes that are responsible for the production, redistribution, and dissipation of these magnetic fields is proposed. These fields are associated with single AGNs within the cluster and therefore with all galaxies during their AGN (active galactic nucleus or quasar) phase, simply because only the central supermassive black holes (∼108M·) formed during the AGN phase have an accessible energy of formation, ∼1061 ergs, that can account for the magnetic field energy budget. An α-Ω dynamo process has been proposed that operates in an accretion disk around a black hole. The disk rotation naturally provides a large winding number, ∼1011 turns, sufficient to make both large gain and large flux. The helicity of the dynamo can be generated by the differential plume rotation derived from star-disk collisions. This helicity generation process has been demonstrated in the laboratory and the dynamo gain was simulated numerically. A liquid sodium analog of the dynamo is being built. Speculations are that the back reaction of the saturated dynamo will lead to the formation of a force-free magnetic helix, which will carry the energy and flux of the dynamo away from the accretion disk and redistribute the field within the clusters and galaxy walls. The magnetic reconnection of a small fraction of this energy logically is the source of the AGN (active galactic nucleus or quasar) luminosity, and the remainder of the field energy should then dominate the free energy of the present-day universe. The reconnection of this intergalactic field during a Hubble time is the only sufficient source of energy necessary to produce an extragalactic cosmic ray energy spectrum as observed in this galaxy, and at the same time allow this spectrum to escape to the galaxy voids faster than the GZK (blackbody radiation) loss

Additional details

Publishing Information

Journal Title
Physics of Plasmas
Journal Volume
8
Journal Issue
5
Journal Page Range
p. 2425-2431
ISSN
1070-664X
CODEN
PHPAEN

Conference

Title
42. annual meeting of the Division of Plasma Physics of the American Physical Society; 10. international congress on plasma physics
Dates
23-27 Oct 2000
Place
Quebec City, PQ (Canada)

INIS

Country of Publication
United States
Country of Input or Organization
International Atomic Energy Agency (IAEA)
INIS RN
34072079
Subject category
S70: PLASMA PHYSICS AND FUSION TECHNOLOGY;
Resource subtype / Literary indicator
Conference
Descriptors DEI
COSMOLOGY; GALAXIES; INTERGALACTIC SPACE; MAGNETIC FIELDS; MAGNETIC RECONNECTION; MAGNETOHYDRODYNAMICS; PLASMA; QUASARS; UNIVERSE
Descriptors DEC
COSMIC RADIO SOURCES; FLUID MECHANICS; HYDRODYNAMICS; MECHANICS; SPACE

Optional Information

Notes
(c) 2001 American Institute of Physics.