PHY 684: RF superconductivity for accelerators

Instructor: Sergey Belomestnykh
Stony Brook University, Fall semester of 2011
2:30 - 3:50, Tu & Th, P119
beginning September 6th classes will be held at BNL in building 911:
2:30 -  4:00 pm, Tuesday, 2nd floor Small Conference Room
1:30 - 3:00 pm, Thursday, 3rd floor Conference Room
Students who do not already work at BNL, please contact the instructor to arrange access to BNL and, if necessary, transportation.

Purpose and Audience

This graduate level course covers application of superconducting radio frequency (SRF) technology to contemporary particle accelerators: storage rings, pulsed and CW linear accelerators (linacs), including energy recovery linacs (ERLs). The course will address physics and engineering aspects of using SRF in accelerators. It will cover fundamentals of RF superconductivity, types of SRF accelerating structures, phenomena limiting performance of those, beam-cavity interactions issues specific to superconducting cavities, different approaches 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.


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 20+ lectures and exercise sessions. Homework problems will be assigned. Homework will be graded and answers provided in the exercise sessions. There will be a 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, cavity geometry optimization, …), 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.


“RF Superconductivity for Accelerators”, by H. Padamsee, J. Knobloch, and T. Hays, John Wiley & Sons, 2nd edition (2008). 

Reading Requirements

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).

Additional suggested reference books and papers: 
“Handbook of Accelerator Physics and Engineering”, edited by A. W. Chao and M. Tigner, World Scientific, 3rd print (2006)
“RF Superconductivity: Science, Technology, and Applications,” by H. Padamsee, Wiley-VCH (2009).
"Introduction to Wakefields and Wake Potentials" by P. B. Wilson, SLAC-PUB-4547 (1989).
"Fundamental-Mode RF Design in e+e- Storage Ring Factories" by P. B. Wilson, SLAC-PUB-6062 (1993).

Credit Requirements

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

Lecture Notes and Homework Problems

August 30 - Lecture 1: Introduction

September 1 - Lecture 2: Brief survey of accelerators
September 6 - Lecture 3: RF fundamentals, part 1
September 8 - Lecture 4: RF fundamentals, part 2
September 13 - Homework #1, due on September 20, before the lecture 
September 13 - Lecture 5: SRF fundamentals, part 1
September 15 - Lecture 6: SRF fundamentals, part 2
September 20 - Lecture 7: Related phenomena
September 22 - Review session
September 27 - Homework #2, due on October 4, before the lecture
September 27 - Lecture 8: SRF system requirements
September 29 - holiday (Rosh Hashanah), no classes

October 4 - Lecture 9: Beam-cavity interaction
October 6 - Review session
October 6 - Lecture 10: Systems engineering, part 1
October 11 - Lecture 11: Systems engineering, part 2
October 13 - Homework #3, due on October 25, before the lecture
October 13 - Lecture 12: Cavity design
October 18 & 20 - no classes
October 25 - Lecture 13: Cryomodule design
October 27 - Review session

November 1 - Lecture 14: Fundamental power couplers
November 3 - Lecture 15: HOM dampers
November 8 - Lecture 16: Frequency tuners
November 10 - Homework #4, due on November 15, before the lecture
November 10 - Lecture 17: Cavity fabrication and processing
November 15 - Lecture 18: High power RF systems
November 17 - Review session
November 24 - holiday (Thanksgiving), no classes

December 1 - Lecture 22: Overview of remaining SRF challenges
December 1 - Take home final exam, due on December 6
December 8 - Closing remarks, review of the final exam (last day of classes)

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