Modeling Accelerator Beam Dynamics Including Superconducting RF Cavities

Modern accelerator designs include superconducting radio frequency (RF) cavities. Although scientists use computer modeling to understand accelerators, it is difficult to achieve sufficiently accurate models of superconducting RF cavities, especially models that include cavity misalignment. This project will combine maps of superconducting RF cavity fields (generated using a self- consistent electromagnetic calculation) with an existing particle tracking code. The existing particle tracking code will then be capable of modeling modern accelerators, including the effects of misalignments. In Phase I, a cavity with relevance to the International Linear Collider (ILC) was modeled using a detailed electromagnetics code, a tool for converting the detailed electromagnetic results into a map appropriate for particle tracking codes was developed, and the map was tested in a particle tracking code for ILC- relevant geometry. Phase II will develop: (1) a full-featured, stand-alone software library from the map generation tool, (2) interfaces with the library to electromagnetic and mapping codes, and (3) a catalog of results for cavity maps of various misalignments and higher-order mode levels. Then, the coupled electromagnetic and mapping codes will be used to study the effects of misalignments and higher-order modes on beam dynamics in ILC- relevant structures. Commercial Applications and Other Benefits as described by the awardee: The development of this tool should lead to consulting opportunities for the ILC, a multi- billion dollar project.