U.S. Particle Accelerator School

Superconducting RF for High-β Accelerators course

Sponsoring University:

Stony Brook University


Superconducting RF for High-β Accelerators


Sergey Belomestnykh and Wencan Xu, Brookhaven National Lab

Purpose and Audience
This graduate level course covers application of superconducting radio frequency (SRF) technology to contemporary high-β accelerators: storage rings, pulsed and CW linacs, including energy recovery linacs (ERLs). The course will address physics and engineering aspects of using SRF in accelerators. It will cover beam-cavity interactions issues specific to superconducting cavities, a systems approach to designing SRF systems and engineering of superconducting cavity cryomodules. The course is intended for graduate students pursuing accelerator physics and graduate engineers and physicists who want to familiarize themselves with superconducting RF systems.

Prerequisites: Classical mechanics, thermodynamics, electrodynamics, and physical or engineering mathematics, all at entrance graduate level.

It is the responsibility of the student to ensure that he or she meets the course prerequisites or has equivalent experience.

Upon completion of this course, the students are expected to understand the physics underlying RF superconductivity and its application to accelerators, the advantages and limitations of SRF technology. The aim is to provide students with ideas and approaches enabling them to evaluate and solve problems related to application of superconducting cavities to accelerators, as well actively participate in engineering of SRF systems for various accelerators.

Instruction Method
This course includes a series of about 20 lectures and exercise sessions. Homework problems will be assigned which will be graded and answers provided in the exercise sessions. There will be an open-book, “take-home” final exam at the conclusion of the course.

Course Content
The course will include a brief introduction of the basic concepts of microwave cavities and the basic concepts of RF superconductivity. Then it will cover the beam-cavity interaction issues in accelerators: wake fields and higher-order modes (HOMs) in superconducting structures, associated with them bunched beam instabilities and approaches to deal with these instabilities (HOM absorbers and couplers, polarized cavities, etc.), bunch length manipulation with SRF cavities, beam loading effects, etc. Following that we will discuss a systems approach and its application to engineering of SRF systems for accelerators. Finally, we will address issues related to engineering of the SRF system components: cryostats, cavities, input couplers, HOM loads, and frequency tuners.

Reading Requirements
(to be provided by USPAS) “RF Superconductivity for Accelerators”, by H. Padamsee, J. Knobloch, and T. Hays, John Wiley & Sons, 2nd edition (2008).
Additional suggested reference books (not provided by USPAS): “Handbook of Accelerator Physics and Engineering”, edited by A. W. Chao and M. Tigner, World Scientific, 3rd print (2006) and “RF Superconductivity: Science, Technology, and Applications,” by H. Padamsee, Wiley-VCH (2009).

It is recommended that students re-familiarize themselves with the fundamentals of electrodynamics at the level of “Fields and Waves in Communication Electronics“ (Chapters 1 through 11) by S. Ramo, J. R. Whinnery, and T. Van Duzer, John Wiley & Sons, 3rd edition (1994) or “Classical Electrodynamics” (Chapters 1 through 8) by J. D. Jackson, John Wiley & Sons, 3rd edition (1999).

Credit Requirements
Students will be evaluated based on the following performances: final exam (50%), homework assignments and class participation (50%).

Stony Brook University course: PHY 543

IU/USPAS course: Physics 671