Perform a survey of the interaction region designs of recently completed colliders and those of proposed colliders both under construction and in future planning. The interaction region issues for both the accelerator and the interface between the detector and accelerator should be covered. Special emphasis should be placed on identifying the needed beam physics, technology limits, and detector requirements and reviewing the extent that they have been addressed in past research. Identify new and promising ideas even if they are in early stages. The group should summarize in a brief report the highest priority research topics and give an approximate time scale for key R&D developments.

Organizing Committee Contacts: A. Dragt, J. Seeman

(i) Superconducting magnets and associated cryogenic and vacuum systems. Review the forefront technological issues in the development of superconducting magnets, together with their associated cryogenic and vacuum systems, for the next generation of high-energy particle accelerators. Examine in detail the most important and challenging aspects of these technologies, both from the point of view of performance and cost-effectiveness. These aspects should include the development and use of superconducting materials (including high temperature superconductors), magnet design for high field quality, magnet fabrication, cryogenic systems and their integration with the magnets, and cold beam vacuum issues. Identify practical and "fundamental" limitations on magnet performance and cost. Prioritize the R&D efforts, in terms of the potential to provide maximal performance and/or cost-effectiveness; determine the major cost drivers for the magnet, cryogenic, and vacuum systems; and establish a technology-limited time line, and the resource requirements, for the R&D efforts.

(ii) Permanent magnets. Review the leading issues in the development of high-performance, low cost permanent magnet systems for the next generation of high-energy particle accelerators. Both high performance magnets for specialized applications and lower cost technologies for large scale applications should be addressed. Specify the principal R&D activities required to address the most challenging issues, prioritize these activities, and establish a technology-limited time line for accomplishing the R&D.

(iii) Magnet power supplies. Examine the principal technical challenges that must be met for magnet power supply systems needed for the next generation of high-energy particle accelerators. Define the principal R&D activities required to meet these challenges, and specify a technology-limited time line for accomplishing the R&D.

Organizing Committee Contacts: G. Dugan, J. Strait

Any of the next generation accelerators will need high power rf sources and rf accelerating systems that transfer ac power to beam power efficiently. The challenges though span a wide range of technologies and rf wavelength. From very low frequency cavities used in Muon Colliders (70 MHz) to very high frequency cavities in Multi TeV linear colliders (30 GHz and more), many of the designs are based on experience and where experience is missing, scaling laws are used. How does Breakdown scale with electric field stength, pulse length and frequency? What limits peak power and effciency in modern power sources?
The experts in this field should generally try to answer these questions and therefore give guidance to the accelerator designers. Limits on fields, peak powers and efficiencies should therefore be an outcome of the working group. Given the experience in the ongoing R&D programs for normal and superconducting cavities the performance achieved today should be described, as well as the limitations and possible cures. The time scale for establishing these cures should be summarized as well. For both, the normal conducting and the superconducting case the subsystems (Modulators, Klystrons, Pulse Compression systems) and cavities should be addressed independently with a description of present status and of the progress being made over the last five years to allow some extrapolation. For the power sources itself, a very active field only partially driven by accelerator builders, future trends and new directions of improvements should be described.
This group should also describe the likely spinoffs of these different technologies into other(and which) fields, coming out of the techncial developments being done in the HEP research environment.

Organizing Committee Contacts: N. Holtkamp, R. Ruth

(i) Positron and antiproton sources. High performance positron sources will be required for the next generation of linear colliders. Antiproton sources are a source of antimatter for proton-antiproton colliders and can provide copious numbers of low energy antiprotons for fundamental research. Review the forefront technological issues in the development of the next generation of positron and antiproton sources. Examine in detail the most important and challenging aspects of these technologies, both from the point of view of performance and cost-effectiveness. What are the new ideas and avenues for sources? Prioritize the R&D efforts, in terms of the potential to provide maximal performance and/or cost-effectiveness; establish a technology-limited time line, and the resource requirements, for the R&D efforts.

(ii) Secondary beams. Although collider experiments dominate the current high-energy physics landscape, high intensity secondary beams of particles still form the basic tools for some important experiments. Review the leading issues and limiting technologies for the development of high-performance secondary beams potentially available from the next generation of high-energy particle accelerators. Identify the secondary beams of interest to the community. Identify the most important R&D efforts that could lead to significant advances in the performance of such secondary beams.

Organizing Committee Contacts: G. Dugan, J. Seeman

Perform a survey of our present understanding of the beam dynamics problems facing the high energy accelerators and colliders, linear or circular, which are currently in operation, currently under construction, or envisioned as a possiblility of the future. The specific beam dynamics areas to be covered are:

Organizing Committee Contacts: A. Chao, A. Dragt, T. Roser

For the next generation of large accelerators, the civil engineering of accelerator tunnels and associated underground enclosures will be a major component of the technical challenge of building such machines. Because of the large scale involved, the engineering will be required to be as cost-effective as possible, and issues such as ground motion and artificial sources of vibration in the environment will need to be carefully considered. Installation and alignment of the machine components will be tasks of unprecedented scope, and will require unprecedented precision. Examine in detail the most important and most difficult aspects of these challenges, both from the point of view of performance and cost-effectiveness. In particular, identify what the site requirements are for the different machines under discussion (NLC, TESLA, VLHC, Muon source), and describe how tunneling methods are affected by them. Identify, for the different types of accelerators, the different length scales that are involved in defining the alignment tolerances, and what are the tolerances over that length scale.. Specify the R&D efforts needed to define the scope of the most critical challenges, and prioritize the efforts, in terms of the potential to provide maximal performance and/or cost-effectiveness. Establish a technology-limited time line, and the resource requirements, for the most important of these efforts.

Organizing Committee Contacts: G. Dugan, N. Holtkamp

Computers have played a larger and larger role in the theory, design and development of accelerators and the associated technologies. Some examples are calculations of beam optics, simulation of instabilities, electromagnetic field calculations, simulation of space-charge dominated beams and halo formation, beam-beam simulations, start-to-end simulations of systems, real-time modeling of accelerators, and simulations of new accelerator ideas such as those involving lasers and plasmas. This group should explore the impact that advanced computational techniques using the most powerful computers would have on research and development in particle beams and accelerator technology. The group should document past success and look at the immediate and long term future of high performance computing as applied to particle beams and accelerator technology. In particular the group should outline a program of proposed research which will bring the world's most powerful computers, and the hardware and software technologies associated with them, to bear on the most challenging and important problems in our field.

Organizing Committee Contacts: C. Joshi, R. Ruth

This group is formed to explore new beam physics and new accelerator technology that are at the forefront of advanced accelerator research and identify those concepts which might open new opportunities for advancement of the energy and luminosity frontier for high energy physics. The group should explore laser-plasma devices, beam-plasma devices, high frequency RF techniques, laser driven accelerators, laser driven particle sources and any other new ideas appropriate to the charge. Finally, the group should identify general research directions that might be especially promising for high-energy physics applications and explore the research necessary to fulfill this promise.

Organizing Committee Contacts: C. Joshi, R. Ruth

Perform a survey of diagnostic systems for high energy particle accelerators and test accelerators for future machines. This group should discuss with other groups to find new and needed diagnostic systems for future accelerators. Special emphasis should be placed on identifying the needed beam physics and technology limits and reviewing the extent that they have been addressed in past research. Identify new and promising ideas even if they are in early stages. The group should summarize in a brief report the highest priority research topics and give an approximate time scale for key R&D developments.

Organizing Committee Contacts: T. Roser, J. Seeman