This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The goals of this project were three-fold: (1) to develop a new capability, based on high performance (parallet to) computers, to perform large scale simulations of high intensity accelerators; (2) to apply this capability to modeling high intensity accelerators under design at LANL; and (3) to use this new capability to improve the understanding of the physics of intense charge particle beams, especially in regard to the issue of beam halo formation. All of these goals were met. In particular, the authors introduced split-operator methods as a powerful and efficient means to simulate intense beams in the presence of rapidly varying accelerating and focusing fields. They then applied these methods to develop scaleable, parallel beam dynamics codes for modeling intense beams in linacs, and in the process they implemented a new three-dimensional space charge algorithm. They also used the codes to study a number of beam dynamics issues related to the Accelerator Production of Tritium (APT) project, and in the process performed the largest simulations to date for any accelerator design project. Finally, they used the new modeling capability to provide direction and validation to beam physics studies, helping to identify beam mismatch as a major source of halo formation in high intensity accelerators. This LDRD project ultimately benefited not only LANL but also the US accelerator community since, by promoting expertise in high performance computing and advancing the state-of-the-art in accelerator simulation, its accomplishments helped lead to approval of a new DOE Grand Challenge in Computational Accelerator Physics.

Advanced high intensity accelerators have important applications in pulsed spallation neutron sources, synchrotron radiation light sources, radioactive ion beam facilities, etc. In contrast to traditional high energy physics accelerators, these high intensity accelerators require very high beam currents with relatively low particle energy. A common practice in the design of high intensity machines is to employ large aperture and short length magnets packed densely along beam lines in limited spaces. As a result, magnetic fringe fields become more profound, and the interference among adjacent magnets often causes problems for machine operation. This has become a new challenge for the design of high-intensity accelerators.This book describes how to solve the problems of magnetic fringe fields and interference, and how to correctly compute particle optics in advanced high intensity accelerators. The book has evolved from the authors research on the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL). The author has developed the theory and technique of 3D-field multipole expansion, assisted by advanced 3D-magnet modeling codes and Mathematica scripts. Advanced 3D-magnet modeling produces accurate, discrete magnetic field data on selected boundaries in magnets. With these simulation data, the 3D-field multipole expansion will produce quasi-analytic field distributions within the boundaries. Furthermore, with mathematical tools, particle optics in magnets can be accurately computed with the fringe fields and interference effects taken into account automatically.The author applied the new theory and technique to the SNS quadrupoles, dipoles, other magnets, and beam transport lines. His new approach also helped to discover and to solve the design problems of the SNS ring injection and extraction during the SNS ring commissioning. These practices are described in great detail in this book, and can be followed by the design of any other accelerator project. In addition, based on the comments and feedback from students and readers, the book also includes many important command input files and Mathematica scripts, which should be very useful and can be directly employed by readers to compute particle optics in their own machines.

This book contains the proceedings of the 1999 ICFA workshop on the physics of high brightness beams. The workshop took a snapshot in time of a fast moving, interdisciplinary field driven by advanced applications such as high gradient, high energy physics linear colliders, high gain free electron lasers, heavy ion fusion, and transmutation of nuclear materials. While the field of high brightness beam physics has traditionally been divided into disparate electron and heavy ion communities, the workshop brought the two types of researchers together, so that a sharing of insights and methods could be achieved. Thus, this book represents a unifying step in the development of the diverse fascinating discipline of high brightness beam physics, with its challenges rooted in collective, nonlinear particle motion and ultra-high electromagnetic energy density.

Advanced high intensity accelerators have important applications in pulsed spallation neutron sources, synchrotron radiation light sources, radioactive ion beam facilities, etc. In contrast to traditional high energy physics accelerators, these high intensity accelerators require very high beam currents with relatively low particle energy. A common practice in the design of high intensity machines is to employ large aperture and short length magnets packed densely along beam lines in limited spaces. As a result, magnetic fringe fields become more profound, and the interference among adjacent magnets often causes problems for machine operation. This has become a new challenge for the design of high-intensity accelerators.This book describes how to solve the problems of magnetic fringe fields and interference, and how to correctly compute particle optics in advanced high intensity accelerators. The book has evolved from the author's research on the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory (ORNL). The author has developed the theory and technique of 3D-field multipole expansion, assisted by advanced 3D-magnet modeling codes and Mathematica scripts. Advanced 3D-magnet modeling produces accurate, discrete magnetic field data on selected boundaries in magnets. With these simulation data, the 3D-field multipole expansion will produce quasi-analytic field distributions within the boundaries. Furthermore, with mathematical tools, particle optics in magnets can be accurately computed with the fringe fields and interference effects taken into account automatically.The author applied the new theory and technique to the SNS quadrupoles, dipoles, other magnets, and beam transport lines. His new approach also helped to discover and to solve the design problems of the SNS ring injection and extraction during the SNS ring commissioning. These practices are described in great detail in this book, and can be followed by the design of any other accelerator project. In addition, based on the comments and feedback from students and readers, the book also includes many important command input files and Mathematica scripts, which should be very useful and can be directly employed by readers to compute particle optics in their own machines.

Physics of Intense Charged Particle Beams in High Energy Accelerators is a graduate-level text — complete with 75 assigned problems — which covers a broad range of topics related to the fundamental properties of collective processes and nonlinear dynamics of intense charged particle beams in periodic focusing accelerators and transport systems. The subject matter is treated systematically from first principles, using a unified theoretical approach, and the emphasis is on the development of basic concepts that illustrate the underlying physical processes in circumstances where intense self fields play a major role in determining the evolution of the system. The theoretical analysis includes the full influence of dc space charge and intense self-field effects on detailed equilibrium, stability and transport properties, and is valid over a wide range of system parameters ranging from moderate-intensity, moderate-emittance beams to very-high-intensity, low-emittance beams. This is particularly important at the high beam intensities envisioned for present and next generation accelerators, colliders and transport systems for high energy and nuclear physics applications and for heavy ion fusion. The statistical models used to describe the properties of intense charged particle beams are based on the Vlasov-Maxwell equations, the macroscopic fluid-Maxwell equations, or the Klimontovich-Maxwell equations, as appropriate, and extensive use is made of theoretical techniques developed in the description of one-component nonneutral plasmas, and multispecies electrically-neutral plasmas, as well as established techniques in accelerator physics, classical mechanics, electrodynamics and statistical physics.Physics of Intense Charged Particle Beams in High Energy Accelerators emphasizes basic physics principles, and the thorough presentation style is intended to have a lasting appeal to graduate students and researchers alike. Because of the advanced theoretical techniques developed for describing one-component charged particle systems, a useful companion volume to this book is Physics of Nonneutral Plasmas by Ronald C Davidson./a