An Advanced Simulation Toolkit for Photon Band Gap/Advanced Structure Development

The development of high-gradient accelerating structures is critical to reducing the cost of next generation particle colliders. In order to develop any novel structure, such as a photo band gap structure, its responses to the drive pulse and to a beam bunch must be fully characterized. This characterization includes the determination of wake-potentials and transient peak surface fields, and an analysis of potential field-emission in high-field regions. Although modeling capabilities for these characterizations have recently been developed, they have yet to integrated and packaged for use by the accelerator community at large. This project will create a specialized modeling toolkit that will be customized for high-gradient structure development, providing access to custom analysis sequences, postprocessing, and design optimization that are specific to advanced structures. In Phase I, a prototype toolkit was created. It contained specialized model templates for creating the complex geometry of photon band gap structures, and it also supported specialized analysis sequences for analyzing photon band gap lattices, cavities, power input couplers, and slow-wave structures. Phase II will add time-domain modeling capabilities to the toolkit, which will greatly extend its utility for advanced structure development, enabling characterization of important effects that are very difficult to determine experimentally. Commercial Applications and other Benefits as described by the awardee: Accurate and sophisticated computer modeling should play a pivotal role if the development of novel structures for efficiently accelerating a charged particle beam. The proposed modeling toolkit will increase the rate of innovation in novel structures, leading to improved, lower cost accelerators for high-energy physics, medical research and therapy, lithography, and other applications.