U.S. Particle Accelerator School
U.S. Particle Accelerator School
Education in Beam Physics and Accelerator Technology

RF Cavity, Component and System for Accelerators


Michigan State University

Course Name:

RF Cavity, Component and System for Accelerators


Alireza Nassiri, Geoff Waldschmidt, Yawei Yang and Branko Popovic, Argonne National Laboratory
TAs: Adam Gleichman and John Wieland, Michigan State University

Purpose and Audience
The purpose of this course is to introduce the students to the design, analysis, and modeling of microwave/radio-frequency systems, cavities and components for charged particle accelerators. An essential background in rf accelerator design and hands-on modeling of RF systems will be attained. This course is suitable for senior and/or graduate students from the fields of physics, applied physics, and electrical engineering who are considering careers in accelerator physics, applied physics or microwave/rf engineering. The course is also appropriate for physicists or engineers working in accelerator-related fields who wish to familiarize themselves with rf engineering.

Courses at the upper division undergraduate level in: Electromagnetism (at the level of “Introduction to Electrodynamics” by David J. Griffiths), and Integral Calculus, and Differential Equations (at the level of “Advanced Calculus” by Gerald B. Folland) are required.  An introduction to Accelerator Science and Technology at the level of USPAS Fundamentals of Accelerator Physics and Technology with Simulations and Measurements Lab is recommended.

It is the responsibility of the student to ensure that they meet the course prerequisites or have equivalent experience.

The objectives of this course are: 1) to review fundamental rf and microwave engineering principles, 2) apply these principles to the design and analysis of rf systems, cavities and components for accelerator applications, 3) learn and become proficient in numerical modeling and rf simulation, 4) use modeling and simulation tools to design and analyze realistic rf components for accelerators, and 5) clarify beam-cavity interactions. Upon completion of this course, students are expected to understand fundamental rf and microwave principles and to be able to successfully design, model, and analyze rf-based accelerator components.

Instructional Method
This course combines a series of twenty lectures with following computer laboratories to accomplish its objectives. The purpose of the lectures is to teach students fundamental concepts through a mathematical treatment and to apply these principles to numerical design, modeling, and measurement of rf components. The instructors will help students familiarize with Microwave Studio - a popular 3D electromagnetic simulation tool that incorporates beam interactions. This is accomplished through interactive and hands-on exercises. Examples employed will help students develop computer skills for rf components and systems. For the computer laboratory sessions, students initially work in small groups and, as they gain experience and expertise, extend work on their own. Students will complete a set of laboratory assignments in addition to daily homework problem sets. The instructors will be available for guidance during evening homework sessions. Students will choose and complete a final design project.

Course Content
Review of essential applied mathematics, basic rf and microwave theory and properties, transmission lines, Smith chart, impedance matching, field analysis of transmission lines, waveguides, accelerating cavities, power couplers, and other resonant structures. Computer laboratory sessions will focus on understanding and using the design and simulation code Microwave Studio. Fundamental topics will include: Maxwell’s equations, Green’s functions, boundary conditions, wave propagation and plane waves, plane wave reflection from a media interface, and dielectric interfaces. Course topics will include: transmission line theory, wave propagation, field analysis in resonant structures, generator and load mismatches, microwave network analysis, microwave resonators, physics of microwave tubes, dielectric and other lossy materials, time harmonic analysis, perturbation and variational techniques, microwave measurements, and impedance. Acceleration by rf systems for linear and circular accelerators including beam / cavity interaction, beam loading, higher-order mode (HOM) effects, and mode damping will be explored. We will overview numerical methods including: finite difference time domain, finite element, numerical stability conditions, and implementation of absorbing boundary conditions.

Reading Requirements
(to be provided by the USPAS) Microwave Engineering, 4th edition, by David M. Pozar, Wiley 2012.

The instructors will provide additional reading materials.

Credit Requirements
Students are evaluated based on the overall course performance: comprehensive final exam (35% course grade), homework assignments (30% course grade), computer lab assignments (20% course grade), and final project (15% course grade).

USPAS Computer Requirements
There will be no Computer Lab and all participants are required to bring their own portable computer to access online course notes and computer resources. This can be a laptop or a tablet with a sufficiently large screen and keyboard. Windows, Mac, and Linux-based systems that are wifi capable and have a standard web browser and mouse are all acceptable. You should have privileges for software installs. If you are unable to bring a computer, please contact uspas@fnal.gov ASAP to request a laptop loan.¬†Very limited IT support and spare loaner laptops will be available during the session.

Michigan State University course number:  PHY 963 Section 703, US Particle Accelerator School
Indiana University course number: Physics 571, Special Topics in Physics of Beams
MIT course number:  8.790, Accelerator Physics