The increasing power of computer resources along with great improvements in observational data in recent years have led to some remarkable and rapid advances in astrophysical fluid dynamics. The subject spans three distinct but overlapping communities whose interests focus on (1) accretion discs and high-energy astrophysics; (2) solar, stellar, and

Although the origin of Earth's and other celestial bodies' magnetic fields remains unknown, we do know that the motion of electrically conducting fluids generates and maintains these fields, forming the basis of magnetohydrodynamics (MHD) and, to a larger extent, dynamo theory. Answering the need for a comprehensive, interdisciplinary introduction

Magnetism is one of the most pervasive features of the Universe, with planets, stars and entire galaxies all having associated magnetic fields. All of these fields are generated by the motion of electrically conducting fluids, the so-called dynamo effect. The precise details of what drives the motion, and indeed what the fluid consists of, differ widely though. In this work the authors draw upon their expertise in geophysical and astrophysical MHD to explore some of these phenomena, and describe the similarities and differences between different magnetized objects. They also explain why magnetic fields are crucial in the formation of the stars, and discuss promising experiments currently being designed to study some of the relevant physics in the laboratory. This interdisciplinary approach makes the book appealing to a wide audience in physics, astrophysics and geophysics.

This book contains the lectures given at the workshop "Dynamo and dynamics, a mathematical challenge" held in Cargese from August 21 to 26, 2000. The workshop differed from most previous conferences on the dynamo effect in two important respects. First, it was at this international conference that the experimental observation of homogeneous fluid dynamos was first reported. Second, the conference gathered scientists from very different fields, thus showing that thepynamo problem has become an interdisciplinary subject involving not only astrophysicists and geophysicists, but also scientists working in dynamical systems theory, hydrodynamics, and numerical simulation, as well as several groups in experimental physics. This book thus reports important results on various dynamo studies in these different contexts: - Decades after the discovery of the first analytic examples of laminar fluid dynamos, the self-generation of a magnetic field by a flow ofliquid sodium has been reported by the Karlsruhe and Riga groups. Although there were no doubts concerning the self generation by the laminar Roberts-type or Ponomarenko-type flows that were used, these experiments have raised interesting questions about the influence of the turbulent fluctuations on the dynamo threshold and on the saturation level of the magnetic field.

1. Prof. Masahiro Wakatani and fusion research in his days / K. Itoh. Magnetic relaxation and self-organization in astrophysical and laboratory plasmas. 2. An introduction to mean field dynamo theory / D. W. Hughes and S. M. Tobias. 3. Origin, structure and stability of astrophysical MHD jets / P.-Y. Longaretti -- Turbulence and turbulent transport - the agents of relaxation and structure formation. 4. A tutorial on basic concepts in MHD turbulence and turbulent transport / P. H. Diamond, S.-I. Itoh and K. Itoh. 5. Intermittency like phenomena in plasma turbulence / A. Das, P. Kaw and R. Jha. 6. Nonlinear cascades and spatial structure of magnetohydrodynamic turbulence / W.-C. Müller and R. Grappin. 7. Scale covariance and scale-ratio covariance in turbulent front propagation / A. Pocheau -- Transport bifurcations and relaxation. 8. Transport barrier relaxations in tokamak edge plasmas / P. Beyer. 9. Dynamics of edge localized modes / X. Garbet ... [et al.]. 10. On the onset of collapse events in toroidal plasmas turbulence trigger / K. Itoh ... [et al.].

Helicities in Geophysics, Astrophysics, and Beyond Helicities play essential roles in numerous geophysical, astrophysical, and magnetohydrodynamic phenomena, thus are studied from various disciplinary viewpoints. Helicities in Geophysics, Astrophysics, and Beyond draws together experts from different research fields to present an interdisciplinary and integrated approach to helicity studies. This synthesis advances understanding of the fundamental physical processes underlying various helicity-related phenomena. Volume highlights include: Concise introduction to fundamental properties of helicities Recent developments and achievements in helicity studies Perspectives from different fields including geophysics, space physics, solar physics, plasma physics, atmospheric and nonlinear sciences A cohesive mathematical, physical, observational, experimental, and numerical strategy for helicity studies A synthesized framework for the application of helicity to real-world problems The American Geophysical Union promotes discovery in Earth and space science for the benefit of humanity. Its publications disseminate scientific knowledge and provide resources for researchers, students, and professionals.