| Author: |
Edith Falgarone & T. Passot
|
| Published in: | Springer Publishing |
| Release Year: | 2003 |
| ISBN: | 0075-8450 |
| Pages: | 462 |
| Edition: | First Edition |
| File Size: | 3 MB |
| File Type: | Djvu |
| Language: | English |
Description of Turbulence and Magnetic fields in Astrophysics
Turbulence and Magnetic fields in Astrophysics contain review articles of most of the topics addressed at the conference on Simulations of Ifiumetahyd, dynamic turbulence in astrophysics: recent achievements and perspectives which took place from July 2 to 6, 2001 at the Institut Henri Poincare in Paris. We made the choice to publish these lectures in a tutorial form so that they can be read by a broad audience. As a result, Turbulence and Magnetic fields in Astrophysics books do not give an exhaustive view of all the subjects addressed during the conference. The rosin objective of this workshop which gathered about 90 scientists from different fields, was to present and confront recent results on the topic of turbulence in magnetized astrophysical environments. A second objective was to discuss the latest generation of numerical codes, such as those using adaptive mesh refinement (AMR) techniques. During a plenary discussion at the end of the workshop, discussions were held on amoral topics, often at the heart of vivid controversies.
Topics included the iime69ftie for the dissipation or magneto-hydrodynamical (MHD) turbulence, the role of boundary conditions, the characteristics of impedance turbulence, the validity of the polytropic approach to Alborn waves support within interstellar clouds, the source of turbulence inside clouds devoid of stellar activity, the timescale for star formation, the Alfizen Mach number of interstellar gas motions, the formation process for helical fields in the interstellar medium. The impact of small upon large scales were also disarmed. Does an incorrect treatment of small scales (e.g. neglect of the Hall effect) affect large wake What is the impact on reconnection? Is there a relationship between the coherent structures of magnetic fields (sheets, tubes...) and the plasma parameter d at the scale considered? What is the effect of magnetic helicity ejection on the dynamo mechanism?
The articles presented in Turbulence and Magnetic fields in Astrophysics book address many of these issues and illustrate the fact that many of them remain open questions. The book has been divided into four chapters. In the fort chapter, general topics in incompressible and compressible MHD turbulence are discussed. These topics include waling laws, intermittency, energy decay, reduced MHD (with a discussion on corona' heating models), a new regime of turbulence at a very large Prandil number and weak turbulence. In particular, the issue of anisotropy and its relation with the Goldreich-Sridhar and the Iroshnikov-Kralchnan theory is fully discussed. The second chapter contains a general discussion of numerical issues in astrophysical MHD turbulence and a presentation of the NIRVANA
Topics included the iime69ftie for the dissipation or magneto-hydrodynamical (MHD) turbulence, the role of boundary conditions, the characteristics of impedance turbulence, the validity of the polytropic approach to Alborn waves support within interstellar clouds, the source of turbulence inside clouds devoid of stellar activity, the timescale for star formation, the Alfizen Mach number of interstellar gas motions, the formation process for helical fields in the interstellar medium. The impact of small upon large scales were also disarmed. Does an incorrect treatment of small scales (e.g. neglect of the Hall effect) affect large wake What is the impact on reconnection? Is there a relationship between the coherent structures of magnetic fields (sheets, tubes...) and the plasma parameter d at the scale considered? What is the effect of magnetic helicity ejection on the dynamo mechanism?
The articles presented in Turbulence and Magnetic fields in Astrophysics book address many of these issues and illustrate the fact that many of them remain open questions. The book has been divided into four chapters. In the fort chapter, general topics in incompressible and compressible MHD turbulence are discussed. These topics include waling laws, intermittency, energy decay, reduced MHD (with a discussion on corona' heating models), a new regime of turbulence at a very large Prandil number and weak turbulence. In particular, the issue of anisotropy and its relation with the Goldreich-Sridhar and the Iroshnikov-Kralchnan theory is fully discussed. The second chapter contains a general discussion of numerical issues in astrophysical MHD turbulence and a presentation of the NIRVANA
0 comments: