Cosmic Plasma

The general background of this monograph and the aim of it is described in detail in Chapter I. As stated in 1.7 it is written according to the principle that "when rigour appears to conflict with simplicity, simplicity is given preference", which means that it is intended for a rather broad public. Not only graduate students but also advanced undergraduates should be able to understand at least most of it. This monograph is the result of many years of inspiring discussions with a number of colleagues, for which I want to thank them very much. Especially I should mention the groups in Stockholm and La Jolla: in Stockholm, Dr Carl-Gunne Flilthammar and many of his collaborators, including Drs Lars Block, Per Carlqvist, Lennart lindberg, Michael Raadu, Staffan Torven, Miroslav Babic, and Itlgvar Axniis, and further, Drs Bo Lehnert and Bjorn Bonnevier, all at the Royal Institute of Technology. Of other col leagues in Sweden, I should mention Dr Bertel Laurent, Stockholm University, Dr Aina Elvius, The Stockholm Observatory, and Dr Bengt Hultqvist, Kiruna. In La Jolla my thanks go first of all to Dr Gustaf Arrhenius, who once invited me to La Jolla, which was the start of a most interesting collaboration; further, to Dr W.B.

This unusual book considers physical principles, starting from the most general ones, and simplifies assumptions, helping students answer two key questions: what approximation is the simplest, but still sufficient for the description of a phenomenon in cosmic plasmas, and how to build an adequate model.

During the past decade our understanding of plasma physics has witnessed an explosive growth due to research in two areas: work directed toward controlled nuclear fusion and work in space physics. This book addresses the growing need to apply these complementary discoveries to astrophysics. Today plasma is recognized as the key element to understanding the generation of magnetic fields in planets, stars and galaxies, the accel- eration and transport of cosmic rays, and many other phenomena occurring in interstellar space, in radio galaxies, stellar atmospheres, quasars, and so forth.

The plan to hold a conference on cosmic plasma physics originated in the Plasma Physics Division of the European Physical Society, whose chairman, B. Lehnert, took the first steps towards its realization. - ESRIN readily adopted this idea, and preliminary contacts with a number of other groups showed that there was a good deal of interest in bringing to gether people working in different areas of the field of cosmic plasma physics. It was clearly felt that an exchange of views and experience, and an attempt to define problem areas, would be profitable. In this spirit a programme was de vised which covered a large variety of topics, ranging from ionospheric to galactic structures. A diversified programme of this kind runs the risk that the communication between the various fields of specialization remains insufficient. It was gratifying to find that within the wide field of cosmic plasma physics a lively dialogue was in fact possible. The Conference was sponsored by the European Physical Society. Financial support was provided by ESRO. It is a pleasure to acknowledge the excellent suggestions of the programme committee members L. Biermann, N. D'Angelo, R. Gendrin, and B. Lehnert. I should like to thank my colleagues B. Bertotti, K. Lackner, and J.F. McKenzie, and numerous other ESRIN staff members, for their valuable help. I feel particularly indebted to the conference secretary, Miss Sachs, who did the real work while I just signed the letters.

This book gives an account of the proceedings of the International Astronomical Union Colloquium 115: High Resolution X-Ray Spectroscopy of Cosmic Plasmas. This was the first IAU meeting dedicated to high resolution X-ray spectroscopy of objects outside the solar system. A broad range of objects and astrophysical conditions are discussed. Results from the first generation of satellites with spectroscopic capability, i.e. the Einstein Observatory, EXOSAT, and Tenma, are reviewed from a perspective of a more precise interpretation allowed by improved theoretical models and plasma diagnostics. Laboratory and solar X-ray results that model or are relevant to conditions found in cosmic X-ray sources are also presented. The colloquium presents a forum for discussion of scientific objectives of new international missions in high resolution X-ray spectroscopy.

This book offers eleven coordinated reviews on multi-scale structure formation in cosmic plasmas in the Universe. Observations and theories of plasma structures are presented in all relevant astrophysical contexts, from the Earth’s magnetosphere through heliospheric and galactic scales to clusters of galaxies and the large scale structure of the Universe. Basic processes in cosmic plasmas starting from electric currents and the helicity concept governing the dynamics of magnetic structures in planet magnetospheres, stellar winds, and relativistic plasma outflows like pulsar wind nebulae and Active Galactic Nuclei jets are covered. The multi-wavelength view from the radio to gamma-rays with modern high resolution telescopes discussed in the book reveals a beautiful and highly informative picture of both coherent and chaotic plasma structures tightly connected by strong mutual influence. The authors are all leading scientists in their fields, making this book an authoritative, up‐to‐date and enduring contribution to astrophysics.

Presents a comprehensive review of physical processes in astrophysical plasmas. This title presents a review of the detailed aspects of the physical processes that underlie the observed properties, structures and dynamics of cosmic plasmas. An assessment of the status of understanding of microscale processes in all astrophysical collisionless plasmas is provided. The topics discussed include turbulence in astrophysical and solar system plasmas as a phenomenological description of their dynamic properties on all scales; observational, theoretical and modelling aspects of collisionless magnetic reconnection; the formation and dynamics of shock waves; and a review and assessment of microprocesses, such as the hierarchy of plasma instabilities, non-local and non-diffusive transport processes and ionisation and radiation processes. In addition, some of the lessons that have been learned from the extensive existing knowledge of laboratory plasmas as applied to astrophysical problems are also covered. This volume is aimed at graduate students and researchers active in the areas of cosmic plasmas and space science. Originally published in Space Science Reviews journal, Vol. 278/2-4, 2013.

Gas at temperatures exceeding one million degrees is common in the Universe. Indeed it is likely that most of the gas in the Universe exists in intergalactic space in this form. Such highly-ionized gas, or plasma, is not restricted to the rarefied densities of intergalactic space, but is also found in clusters of galaxies, in galaxies themselves, in the expanding remnants of exploded stars and at higher densities in stars and the collapsed remains of stars up to the highest densities known, which occur in neutron stars. The abundant lower-Z elements, at least, in such gas are completely ionized and the gas acts as a highly conducting plasma. It is therefore subject to many cooperative phenomena, which are often complicated and ill-understood. Many of these processes are, however, well-studied (if not so well-understood) in laboratory plasmas and in the near environment of the Earth. Astronomers therefore have much to learn from plasma physicists working on laboratory and space plasmas and the parameter range studied by the plasma physicists might in turn be broadened by contact with astronomers. With that in mind, a NATO Advanced Research Workshop on Physical Processes in Hot Cosmic Plasmas was organized and took place in the Eolian Hotel, Vulcano, Italy on May 29 to June 2 1989. This book contains the Proceedings of that Workshop.