Significant advances have been made recently in both the theoretical understanding and observation of small-scale turbulence in different layers of the Sun, and in the instabilities that give rise to them. The general development of solar physics, however, has led to such a degree of specialization as to hinder interaction between workers in the field. This book therefore presents studies of different layers and regions of the Sun, but from the same aspect, concentrating on the study of small-scale motions. The main emphasis is on the common theoretical roots of these phenomena, but the book also contains an extensive treatment of the observational aspects.

Over the last decade we entered a new exploration phase of solar flare physics, equipped with powerful spacecraft such as Yohkoh, SoHO, and TRACE that pro vide us detail-rich and high-resolution images of solar flares in soft X-rays, hard X -rays, and extreme-ultraviolet wavelengths. Moreover, the large-area and high sensitivity detectors on the Compton GRO spacecraft recorded an unprecedented number of high-energy photons from solar flares that surpasses all detected high energy sources taken together from the rest of the universe, for which CGRO was mainly designed to explore. However, morphological descriptions of these beau tiful pictures and statistical catalogs of these huge archives of solar data would not convey us much understanding of the underlying physics, if we would not set out to quantify physical parameters from these data and would not subject these measurements to theoretical models. Historically, there has always been an unsatisfactory gap between traditional astronomy that dutifully describes the mor phology of observations, and the newer approach of astrophysics, which starts with physical concepts from first principles and analyzes astronomical data with the goal to confirm or disprove theoretical models. In this review we attempt to bridge this yawning gap and aim to present the recent developments in solar flare high-energy physics from a physical point of view, structuring the observations and analysis results according to physical processes, such as particle acceleration, propagation, energy loss, kinematics, and radiation signatures.

Significant advances have been made recently in both the theoretical understanding and observation of small-scale turbulence in different layers of the Sun, and in the instabilities that give rise to them. The general development of solar physics, however, has led to such a degree of specialization as to hinder interaction between workers in the field. This book therefore presents studies of different layers and regions of the Sun, but from the same aspect, concentrating on the study of small-scale motions. The main emphasis is on the common theoretical roots of these phenomena, but the book also contains an extensive treatment of the observational aspects.

Markus Aschwanden introduces the concept of self-organized criticality (SOC) and shows that due to its universality and ubiquity it is a law of nature for which he derives the theoretical framework and specific physical models in this book. He begins by providing an overview of the many diverse phenomena in nature which may be attributed to SOC behaviour.

The author then introduces the classic lattice-based SOC models that may be explored using numerical computer simulations. These simulations require an in-depth knowledge of a wide range of mathematical techniques which the author introduces and describes in subsequent chapters. These include the statistics of random processes, time series analysis, time scale distributions, and waiting time distributions. Such mathematical techniques are needed to model and understand the power-law-like occurrence frequency distributions of SOC phenomena. Finally, the author discusses fractal geometry and scaling laws before looking at a range of physical SOC models which may be applicable in various aspects of astrophysics. Problems, solutions and a glossary will enhance the pedagogical usefulness of the book.

SOC has been receiving growing attention in the astrophysical and solar physics community. This book will be welcomed by students and researchers studying complex critical phenomena.

Solar science has evolved rapidly over the past ten years as the results of a new generation of solar space missions have become available. This book provides a thorough introduction to the subject of solar physics, based on those spacecraft observations. The author introduces the solar corona, which has a temperature of several million degrees, and sets it in the context of basic plasma physics before moving on to discuss plasma instabilities and plasma heating processes. The latest results on coronal heating and radiation, which are fundamental processes in all stars, are presented. Spectacular phenomena such as solar flares and coronal mass ejections are described in detail, together with their potential effects on the Earth. The author draws together observations made at many wavelengths from hard X-rays, soft X-rays, extreme UV and radio wavelengths.

This paperback study edition of Markus Aschwanden s highly acclaimed Physics of the Solar Corona will include 50 pages of problems and solutions which will much enhance the value of the book to students."