Positron Annihilation - ICPA-10 presents new results and ideas of researchers who seek more profound understanding of the nature of positron annihilation. All these scientific and technological thoughts are included in these two-volume proceedings, which contain 7 review talks, 203 contributed papers (among them, 20 are invited), and 3 summary talks. The volume is complete with keyword and author indices.

Selected, peer reviewed papers from the 17th International Conference on Positron Annihilation (ICPA-17), September 20-25, Wuhan, China

Proceedings of the 10th International Conference on Positron Annihilation (ICPA-10) held in Beijing, China, May 1994

This book provides a comprehensive and up-to-date account of the field of low energy positrons and positronium within atomic and molecular physics. Each chapter contains a blend of theory and experiment, giving a balanced treatment of all the topics. Useful for graduate students and researchers in physics and chemistry.

For one and a half decades, the application of positron annihilation to condensed-matter physics concentrated on the study of the Fermi surfaces of metals and alloys. As other, often more powerful, techniques for performing this type of study were developed, it appeared that condensed-matter positron physics was going to be relegated to being a niche interest. However, the situation changed dramatically when it was found that measurements of positron annihilation in metals were sensitive to the structures of well-known defects. This discovery, and subsequent research made it a major tool in materials science.

The book is intended to describe the basic and newly developed elements of the physics of solids and materials science on mechanical properties of metals with as much continuity as is possible. Particular emphasis has been placed in atomistic and fractal approaches and continuum theory of dislocations is also introduced. Since the book is meant for the two main topics of progress in recent years, some interesting and important topics which have not been discussed or introduced are given in detail.For a long time, pair potentials were used very expensively in simulation studies. They can reproduce usefully total energies for many systems. But when one turns to elastic properties, fracture of surfaces, and the vacancy formation energy, deficiencies and limitations begin to emerge. These limitations of the simple pair potential approximation have been addressed by the development of empirical many-body potentials which is the major theme of our book.Over a decade or more, diverse scientists have recognized that many of the structures common in their experiments have a special kind of geometrical complexity. The key to this progress is the recognition that many random structures obey a symmetry that objects look the same on many different scales of observation. The concept of fractals was introduced by Mandelbrot and applied to fractures by himself and collaborators. Their work pointed to a correlation between toughness and the fractal dimension. Our interest is the fractal aspects of fractured surfaces. We will discuss more in our book.The strain field of a dislocation has a long range part and this part can be discussed rigorously from elasticity theory. Recent progress in elastic strain fields and dislocation mobility were made by Indenbom and Lothe. The elementary essentials will be introduced in our book.

There is no doubt that, when it comes to the study of the structures and defects of materials, there is presently no technique that rivals positron annihilation. The increasing demands for higher accuracy and reliability provide a constant stimulus to the field, and the present work presents the newest and most important scientific discoveries made in the field of positron annihilation. Many important new results concerning positron and positronium studies of nano-materials, defects, porous materials, low-k dielectrics, polymers, liquids, atomic physics and new instrumentation are reported in the present contributions; presented by experts from all over the world. There can be no better way of keeping up with this rapidly advancing field.

The only critical discussion available on the chemistry of the two "strange" light particles, the positron and positronium, with much space devoted to the excess electron. Positron annihilation allows the investigation of many unusual phenomena in the reaction kinetics of the positron, positronium, and excess electron, and in radiation chemistry and physics, while also providing important information on defects in solids.

This workshop on the subject of positron and positronium chemistry is the third international conference after those in Blacksburg, Virginia (1979), and in Arlington, Texas (1986). The fields of interests are interdisciplinary, such as radiation chemistry, superconductivity polymer chemistry, biochemistry, quantum chemistry and nuclear chemistry.