Magnetic Fields of GalaxiesSpringer Science & Business Media, 31 mag 1988 - 313 pagine Magnetism, when extended beyond normal frameworks into cosmic space is characterized by an enormous spatial scale. Because of their large sizes the nature of magnets such as the Earth and the Sun is entirely different from the nature of a horseshoe magnet. The source of cosmic magnetism is associated with the hydrodynamic motions of a highly conductive medium. In this aspect, cosmic magnets resemble a dynamo. However, currents in the dynamo flow along properly ordered wires, while chaotic, turbulent motions are dominant inside stars and liquid planetary cores. This makes more intriguing and surprising the fact that these motions maintain a regular magnetic field. Maintenance of magnetic fields is even more impressive in huge magnets, i.e. galaxies. In fact, we are living inside a giant dynamo machine, the Milky Way galaxy. Although the idea of the global magnetic field of our Galaxy was clearly proposed almost 40 years ago, firm observational evidence and definite theoretical concepts of galactic magnetism have been developed only in the last decade. This book is the first attempt at a full and consistent presentation of this problem. We discuss both theoretical views on the origin of galactic magnetism and the methods of observational study. Previous discussions were on the level of review articles or separate chapters in monographs devoted to cosmic magnetic fields (see, e.g., H. K. Moffatt, 1978, E. N. Parker, 1979 and Zeldovich et aI., 1983). |
Sommario
CHAPTER I | 1 |
CHAPTER II | 7 |
112 Spiral Galaxies | 11 |
II3 Gas and Dust | 12 |
II4 Cosmic Rays | 17 |
CHAPTER III | 20 |
III2 Polarization of Synchrotron Emission | 24 |
III3 Faraday Rotation | 32 |
VI4 Mean Hclicity | 162 |
VI5 Magnetic Fields and Star Formation | 166 |
CHAPTER VII | 171 |
VII2 The Mean Magnetic Field | 172 |
VII3 Evolution of Magnetic Field in a Moving Medium | 173 |
VII4 The Equation for the Mean Magnetic Field | 177 |
VII5 Field Distribution Across the Disc | 181 |
VII6 Radial Field Distribution in Discs of Variable Thickness | 191 |
III4 Light Polarization by Dust | 37 |
1115 Zeeman Splitting | 47 |
III6 Other Methods | 53 |
III7 Discussion | 54 |
CHAPTER IV | 57 |
IV2 How the Magnetic Field is Derived from Faraday Rotation Data | 64 |
IV3 The Largescale Magnetic Field of the Galaxy According to Faraday Rotations of Extragalactic Sources | 71 |
IV4 The Fluctuation Magnetic Field in the Galaxy | 79 |
IV5 The Structure of the LargeScale Field | 80 |
IV6 Intensity Variations of the Galactic Nonthermal Radio Background | 81 |
IV7 Magnetic Fields in Nearby Spiral Galaxies | 85 |
CHAPTER V | 95 |
V2 The Relic Field Hypothesis | 97 |
V3 Cosmological Magnetic Fields | 103 |
V4 Stellar Ejections | 109 |
V5 The Dynamo | 113 |
GALACTIC HYDRODYNAMICS | 122 |
VI2 Shape of the Gaseous Disc | 133 |
VI 3 Interstellar Turbulence | 142 |
VII7 Radial Distribution of Axisymmetric Fields in Spiral Galaxies | 200 |
VII8 Generation of NonAxisymmetric Magnetic Fields in an Axisymmetric Disc | 209 |
VII9 The Origin of LargeScale Bisymmetric Magentic Structures | 224 |
VII10 LargeScale Magnetic Fields in Rigidly Rotating Objects | 233 |
VII11 Magnetic Fields Within Spiral Arms | 242 |
VII12 Nonlinear Effects in the Galactic Dynamo | 246 |
VII13 Generation of Fluctuation Fields | 248 |
VII14 Seed Fields | 255 |
CHAPTER VIII | 261 |
VIII2 Magnetic Fields in Clusters of Galaxies | 264 |
CHAPTER IX | 269 |
IX2 Quasars and Active Galactic Nuclei | 271 |
IX3 Radiogalaxies | 274 |
IX4 Jets | 278 |
CHAPTER X | 284 |
286 | |
311 | |
Altre edizioni - Visualizza tutto
Magnetic Fields of Galaxies A.A. Ruzmaikin,D. D. Sokoloff,A. M. Shukurov Anteprima non disponibile - 2014 |
Magnetic Fields of Galaxies A.A. Ruzmaikin,D.D. Sokoloff,A.M. Shukurov Anteprima non disponibile - 2011 |
Parole e frasi comuni
angular velocity approximation Astron Astrophys asymptotic average azimuthal cm³ configuration coronae correlation cosmic rays differential rotation diffusion disc thickness distance dynamo number dynamo theory eigenfunctions equation estimate extragalactic Faraday rotation field component Figure fluctuations function galactic disc galactic magnetic fields gaseous disc growth rate half-thickness HII regions intercloud interstellar gas interstellar magnetic fields interstellar medium interstellar turbulence ionized km s¹ large-scale field large-scale magnetic field linear magnetic field strength magnetic lines mean helicity modes molecular clouds Nebula neutral hydrogen non-axisymmetric observed obtained parameters particles plane polarization degree position angle pulsars radio radioemission radiohalos radiosources radius random region relativistic electrons Reynolds number rotation curve rotation measures Ruzmaikin scale Section shock waves Shukurov solution sources spectral spectrum spiral arms spiral galaxies spiral pattern star formation stellar supernova symmetry synchrotron emission turbulent motions velocity field wavelength Zeeman Zeeman effect
Brani popolari
Pagina 310 - A Search for a Linearly Polarized Component of the Galactic Radio Emission at 408 Mc/s', Observatory 82, 158—164.
Pagina 309 - The Distribution of Atomic Hydrogen in the Outer Parts of the Galactic System", Bull.
Pagina 303 - ... the gas content of galaxies. Astrophys. J. 176:L9-L14, 1972. 39. REEVES, H., J. AUDOUZE, WA FOWLER, and DN SCHRAMM. On the origin of light elements. Astrophys. J. 179:909, 1973. 40. RINGWOOD, AE Origin of the Moon. (Clarke Memorial Lecture) Earth Planet. Sci. Lett. 8: 131-140, 1970. 41. ROBERTS, WW Large-scale shock formation in spiral galaxies and its implications on star formation.