Inelastic scattering of X-rays with very high energy resolution has finally become possible thanks to a new generation of high-intensity X-ray sources. This development marks the end to the traditional belief that low energy excitations like lattice vibrations cannot be resolved directly with X-rays: Inelastic scattering experiments allow to observe directly the small energy shifts of the photons. Studies of lattice vibrations, of excitations in molecular crystals, of collective excitations in liquids and electronic excitations in crystals demonstrating the broad applicability and power of this new technology are discussed in this book. The progress in this field opens up fantastic new research areas not only in physics but also in other disciplines such as materials science, biology and chemistry.

Neutron radiography has in recent years emerged as a useful and complementary technology for radiation diagnosis. It is now routinely used in industrial quality assurance and in support of selected research and developmental activities. Conferences are held on the subject, pertinent handbooks exist, and technical papers appear regularly reporting on new developments. While neutron radiography has indeed passed through the transition from a scientific curiosity to technological relevance, it is a sign of its continuing dynamic evolution that little material has appeared which provides an integrated mathematical and physical analysis of the subject possessing both an instructional as well as reference function. It is our hope that this monograph will fill this need. The distinctiveness of neutron radiography rests on the unique interactions between neutrons and nuclei. This leads to some special relationships between the material and geometrical properties of an object and the neutron radiographic image. The evolution of a technical discipline demands that specific conceptual constructs be developed and their mathematical representations examined and compared with controlled experiments. Experience has convinced us that a particular and substantial body of knowledge has accumulated endowing neutron radiography with the essential foundations of a unique mathematical and physical science. Our scientific and professional involvement in neutron radiography began some 15 years ago when the senior author (A.A.H.) found himself with convenient access to the McMaster University Nuclear Reactor and research support from the Government of Canada.

Edgard Gunzig and Pasquale Nardone RGGR Universite Libre de Bruxelles CP231 1050 Bruxelles Belgium The NATO Advanced Research Workshop on "The Origin of Structure in the Universe" was organized to bring together workers in various aspects of relativistic cosmology with the aim of assessing the present status of our knowledge on the formation and evolution of structure. As it happened, the meeting was particularly timely. Only two days before the 30 or so physicists from many countries gathered for a week at the Chateau du Pont d'Oye, in the forests of the southern Belgian province of Luxembourg, newspaper headlines all over the world announced the results of the analysis of the first full year of data from the Cosmic Background Observer Satellite (COBE). This long-awaited confirmation of the theoretically predicted anisotropy in the microwave background radiation opened a new era in observational cos mology. The realization of the new relevance of the subject of the workshop and the questions raised by the observational results, in addition to bring ing TV crews and newspaper journalists, naturally influenced and stimulated many discussions among the participants. The success of the meeting as usual is due to a combination of factors. Besides the high quality of the talks, discussions were encouraged by the warm atmosphere of the Chateau, for which we are grateful to Mme. Camille Orts, and its beautiful surroundings, not to mention the marvelous cuisine.

The Imager for Magnetopause-to-Aurora Global Exploration (IMAGE) is a NASA Explorer mission that is the first space mission dedicated to imaging of the Earth's magnetosphere. IMAGE was launched from Vandenberg AFB into an elliptical polar orbit by a Delta II launch vehicle on March 25, 2000. The two-year prime sci entific mission of IMAGE began on May 25, 2000 after instrument commissioning was successfully completed. IMAGE has now been approved for operation until October 1,2005, and an additional two-year extension is now being considered by NASA. The papers in this volume represent many of the scientific results obtained dur ing the IMAGE prime mission and include some of the early correlative research with ground-based measurements, measurements from other spacecraft such as Cluster II, and relevant theory and modeling programs. All of the reported work is related to the overall IMAGE science objective: How does the magnetosphere respond globally to the changing conditions in the solar wind? IMAGE addresses this question with multi-spectral imaging of most of the important plasma pop ulations of the inner magnetosphere, combined with radio sounding of gradients of total plasma content. The new experimental techniques fall into the following areas: neutral atom imaging (NAI) over an energy range from 10 eV to 500 keY for detection of ionospheric outflow, the plasma sheet, and the ring current; far ultraviolet (FUV) imaging at 121-190 nm for detection of precipitating protons and the global aurora; extreme ultraviolet (EUV) imaging at 30.

The broad field of conformational motion disorder in crystals is described with particular attention to the separation from the well known mesophases of liquid crystals and plastic crystals. Structure, thermodynamics and motion of a larger number of small and large molecules are discussed. Of special interest are the borderlines between smectic and high viscosity liquid crystals and condis crystals and between plastic crystals and condis crystals as complicated by pseudorotation, jumping between symmetry-related states and hindered rotation. This paper illustrates the wide distribution of conformational disorder in nature. Condis crystals and glasses ("Con"formational "Dis"order) can be found in small and large molecule systems made of organic, inorganic and biological compounds. The condis state was newly discovered only four years ago. In this article over 100 examples are discussed as example of the condis state. In many cases the condis state was suggested for the first time. Motion in the Condensed State, Condis Crystals and their Relation to Plastic Crystals, Condis Crystals of Flexible Macromolecules, Condis Crystals and their Relation to Liquid Crystals, Condis Crystals of Stiff Macromolecules.

The Aharonov-Bohm effect is associated with cyclic motion. It is one of a number of anholonomic effects, and this means that the dynamical description depends on the current position of the system and on the path by which it reached that position.
An example of an anholonomic effect is Foucault's famous pendulum, which simply demonstrates the Earth's rotation. The Sagnac effect - a light beam passing around a rotated system of mirrors - is another example. Modern dynamical developments such as Hannay's angle and Berry's phase are further useful examples.

Measuring the hydrogen content in materials is important both for research and for various applications in material and surface sciences, such as hydrogen embrittlement of steel, controlled thermonuclear reaction first wall studies, and changed material properties caused by dissolved hydrogen. Hydrogen is the most difficult atomic species to analyze by traditional methods, but nuclear physics methods are particularly suited for this purpose. President of the Uzbek SSR Academy of Sciences P.K. Khabibullaev and Professor B.G. Skorodumov discuss in this book the characteristics of these methods, such as lower detection limits, selectivity in respect to different isotopes, accuracy, depth resolution and maximum detection depth. Examples of applications that are dealt with include the determination of material humidity, the dating of objects, the study of hydrogen diffusion including non-stationary processes, and the investigation of changes in material properties like superconductivity, plasticity and electrical properties due to contamination by hydrogen.

This volume contains the invited and contributed papers presented at the Fourth International Conference on Perspectives in Hadronic Physics and sent to the Editors within the deadline. The Conference was held at the Abdus Salam International Centre for Theoretical Physics (ICTP), Trieste, Italy, from May 12th to 16th, 2003, and was attended by about 100 scientists from 20 countries. The series ofConferences on Perspectives on Hadronic Physics takes place every two years since 1997 and follows the seven Workshops on Perspectives in Nuclear Physics at Intermediate Energies, organized every two years at ICTP since 1983. The aim of these Conferences is to discuss the status-of-the-art concerning the experimental and theoretical investigations of hadronic systems, from nucleons to nuclei and dense nuclear matter, in terms of the relevant underlying degrees of freedom. For such a reason the Fourth Conference has been focused on those experimental and theoretical topics which have been in the last few years the object of intensive investigations, viz. the various approaches employed to describe the structure of hadrons in terms of QCD and QCD inspired models, the recent developments in the treatment of the properties and propagations of hadronic states in the medium, the relevant progress done in the solution of the few- and many- hadron problems, the recent results in the experimental investigation of dense hadronic matter and, last but not least, the physics programs of existing Laboratories and the suggested projects for new Facilities.

Physicists who wish to understand the modeling of confinement of quantum chromodynamics, as exhibited by dual superconductors, will find this book an excellent introduction. The author focuses on the models themselves, especially the Landau--Ginzburg model of a dual superconductor, also called the Dual Abelian Higgs model.

Computer simulation has become a basic tool in many branches of physics such as statistical physics, particle physics, or materials science. The application of efficient algorithms is at least as important as good hardware in large-scale computation. This volume contains didactic lectures on such techniques based on physical insight. The emphasis is on Monte Carlo methods (introduction, cluster algorithms, reweighting and multihistogram techniques, umbrella sampling), efficient data analysis and optimization methods, but aspects of supercomputing, the solution of stochastic differential equations, and molecular dynamics are also discussed. The book addresses graduate students and researchers in theoretical and computational physics.

Photoproduction of pions from complex nuclei has become an investigative tool for (1) the detailed form of the elementary photopion amplitude, (2) the pion-nucleus optical potential, (3) nuclear structure, and (4) off-shell and medium effects on the elementary amplitude in nuclear processes. In this book, all these aspects are considered in detail. With improved experimental accuracy and beam tech- nology the study of nuclear pion photoproduction will break new ground and become an even more powerful investigative tool. This monograph is intended as an introductory guide as well as a reference manual for grad- uate students and researchers working in this important area of physics.

Nuclear magnetic resonance spectroscopy, which has evolved only within the last 20 years, has become one of the very important tools in chemistry and physics. The literature on its theory and application has grown immensely and a comprehensive and adequate treatment of all branches by one author, or even by several, becomes increasingly difficult. This series is planned to present articles written by experts working in various fields of nuclear magnetic resonance spectroscopy, and will contain review articles as well as progress reports and original work, its main aim, however, is to fill a gap, existing in literature, by publishing articles written by specialists, which take the reader from the introductory stage to the latest development in the field. The editors are grateful to the authors for the time and effort spent in writing the articles, and for their invaluable cooperation. The Editors Contents P. Diehl and C. L. Khetrapal NMR Studies of Molecules Oriented in the Nematic Phase of Liquid Crystais......................................................... 1 R. G. Jones The Use of Symmetry in Nuclear Magnetic Resonance................. 97 NMR Studies of Molecules Oriented in the Nematic Phase of Liquid Crystals P. DIEHL and C. L. KHETRAPAL * Department of Physics, University of Basel, Switzerland Contents 1. Introduction . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Liquid Crystals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 . . . . . . . . . . . . . . 2.1. Classification of Liquid Crystal Phases . . . . . . . . . . . . . . . . . . . . . . . 4 2.2. Theories of the Liquid Crystalline State . . . . . . . . . . . . . . . . . . . . . . 5 2.3. Nematic Phases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3. Experimental . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 1 4. Basic Theory (for I = I ). . . . . . . . . . . . . * . . . . . . . . . . . . . . . . . . . . . . . 7 . .

This book is intended to give an introduction to intermolecular forces from an experimental point of view. Within the last 10 years the interest has turned more and more into an understanding of the weak, but important, int- molecular forces. New experimental techniques have been developed which have helped to gain more insight into this interesting topic. This book is intended as an introduction for graduate students who are familiar with the main concepts of n olecular spectroscopy. Special emphasis will be laid on the theoretical concepts. After a detailed description of experimental techniques, the results for two prototype systems which have been the subject of several studies in the literature within recent years will be presented. Ar-CO is becoming the most extensively studied van der Waals complex, theoretically and experimentally. Nevertheless, this example shows that even though the theory has greatly improved and has helped us to improve our knowledge of intermolecular forces, even for relatively simple cases the theory car1 still fall short of an accurate description. For a long time (NH3)2 was considered as a prototype for hydrogen bo- ing. However, subsequent experimental and theoretical studies have revealed the mysteries of the obtained spectra and proved that our previous concept of hydrogen bonds was just too naive.

For more than a century, studies of atomic hydrogen have been a rich source of scientific discoveries. These began with the Balmer series in 1885 and the early quantum theories of the atom, and later included the development of QED and the first successful gauge field theory. Today, hydrogen and its relatives continue to provide new fundamental information, as witnessed by the contributions to this book. The printed volume contains invited reviews on the spectroscopy of hydrogen, muonium, positronium, few-electron ions and exotic atoms, together with related topics such as frequency metrology and the determination of fundamental constants. The accompanying CD contains, in addition to these reviews, a further 40 contributed papers also presented at the conference "Hydrogen Atom 2" held in summer 2000. Finally, to facilitate a historical comparison, the CD also contains the proceedings of the first "Hydrogen Atom" conference of 1988. The book includes a foreword by Norman F. Ramsey.

Powerful new techniques, including heavy ion and exotic beams, are pushing the frontiers of nuclear physics and opening up a wealth of new fields of research. After introductory chapters on theoretical and experimental aspects of nuclear collisions and beams, Exotic Nuclear Physics'' offers articles by experienced lecturers on forefront topics in nuclear physics, such as the conquest of the neutron and the proton drip-lines, nuclear astrophysics, the equation of state of hypernuclear matter, nuclear supersymmetry and chaotic motion in nuclei. This volume continues the successful tradition of published lecture notes from the Hispalensis International Summer School. It will benefit graduate students and lecturers in search of advanced material for self-study and courses as will as researchers in search of a modern and comprehensive source of reference.

A variety of novel applications for the investigation of disordered surfaces by beams of thermal energy atoms are discussed and illustrated by numerous examples. A straightforward semiclassical approach is introduced to yield a remarkably detailed insight into the lateral distributions of diffuse scatterers such as adsorbates, vacancies and atomic steps. The recent discovery that the long range Van der Waals force is the cause of the unusually large cross-sections for diffuse He-scattering on individual defects and impurities led the authors to propose a new methods of surface analysis. They introduce a semiclassical method, the overlap approach, to give a simple and detailed description of He-scattering from disordered surfaces. The method yields subtle, otherwise hardly obtainable information on the nature of interactions between diffuse scatterers. The authors address such questions as the lateral distribution of adsorbates, two-dimensional phase transitions, surface diffusions, and the morphology of growing or sputtered layers.

Photothermal science continues to be an area of rapid development and active investigation, as is demonstrated by this volume. The various contributions present fundamental research in materials science, physics, chemistry, biology, and medicine, as well as important applications of photothermal techniques in nondestructive evaluation, aeronomy and pollution control, and other areas. The topics treated include measurements of spectral properties of gases, the theory of thermally generated elastic waves, a method of monitoring local surface displacements, materials characterization and nondestructive evaluation of materials, studies of the dynamics of primary photophysical processes, fast energy exchange at surfaces and at interfaces (e.g. in medicine and photobiology), thermal EXAFS and XANES applied to metals and semiconductors, and imaging of magnetic materials using microwave sources.

Quantum physics has turned our commonsense notion of reality on its head. This accessible book describes in layperson's terms the strange phenomena that exist at the quantum level--a world of tiny dimensions where nothing is absolutely predictable, where we rethink causality, and information seemingly travels faster than light. The author, a veteran physicist, uses illuminating analogies and jargon-free language to illustrate the basic principles of the subatomic world and show how they explain everything from the chemistry around us to the formation of galaxies. He also explains how scientists and engineers interact with this nebulous reality and, despite its mysteries, achieve results of great precision.Up front is a brief history of the early 20th-century "quantum revolution," focusing on some of the brilliant individuals whose contributions changed our view of the world--Albert Einstein, Niels Bohr, Paul Dirac, Werner Heisenberg, Erwin Schroedinger, and others. The work concludes with a discussion of the many amazing inventions that have resulted from quantum theory, including lasers, semiconductors, and the myriad of electronic devices that use them.Lucidly written, this book conveys the excitement of discovery while expanding the reader's appreciation for a science that explores the basis of everything we know.