The field of cluster science is currently attracting considerable interest, not only from a fundamental standpoint, but also through its future applications to electronic, optical, magnetic, and other devices. Synthesizing specific clus­ ters as a unit of useful nanostructures or controlling them as an assembly of nanocomposites is one of the ultimate purposes in this field. In order to understand how to synthesize individual clusters and t_o investigate physical properties, chemical reactions, structural stability, response to external fields, aggregation, phase transition, and other aspects of clusters, a great deal of effort has gone into experiment, theory and computer simulation in this area. This is presumably motivated by the fact that a high level of collaboration between theoretical and experimental researchers is particularly important for progress in the field of cluster science. The present book aims to collect together recent advances in this rapidly growing field.

Since the early days of modem physics spectroscopic techniques have been employed as a powerful tool to assess existing theoretical models and to uncover novel phenomena that promote the development of new concepts. Conventionally, the system to be probed is prepared in a well-defined state. Upon a controlled perturbation one measures then the spectrum of a single particle (electron, photon, etc.) emitted from the probe. The analysis of this single particle spectrum yields a wealth of important information on the properties of the system, such as optical and magnetic behaviour. Therefore, such analysis is nowadays a standard tool to investigate and characterize a variety of materials. However, it was clear at a very early stage that real physical compounds consist of many coupled particles that may be excited simultaneously in response to an external perturbation. Yet, the simultaneous (coincident) detection of two or more excited species proved to be a serious technical obstacle, in particular for extended electronic systems such as surfaces. In recent years, however, coincidence techniques have progressed so far as to image the multi-particle excitation spectrum in an impressive detail. Correspondingly, many-body theoretical concepts have been put forward to interpret the experimental findings and to direct future experimental research. This book gives a snapshot of the present status of multi-particle coincidence studies both from a theoretical and an experimental point of view. It also includes selected topical review articles that highlight the achievements and the power of coincident techniques.

Following the pioneering discovery of alpha clustering and of molecular resonances, the field of nuclear clustering is today one of those domains of heavy-ion nuclear physics that faces the greatest challenges, yet also contains the greatest opportunities.

Scalable Coherent Interface (SCI) is an innovative interconnect standard (ANSI/IEEE Std 1596-1992) addressing the high-performance computing and networking domain.