PHY543 spring 2023

Class meet time and dates	Instructors
When: M, 6:05 pm - 9:00pm Where: The course is taught remotely via Zoom. A Zoom meeting link was sent to registered students via email before the first lecture.	Prof. Sergey Belomestnykh Prof. Irina Petrushina Dr. Silvia Verdu Andres

Course Overview

This graduate level course covers application of radio frequency (RF) superconductivity to contemporary particle accelerators: particle colliders, storage rings for X-ray production, pulsed and CW linear accelerators (linacs), energy recovery linacs (ERLs), etc. The course will address both physics and engineering aspects of the field. It will cover fundamentals of RF superconductivity, types of superconducting radio frequency (SRF) accelerating structures, performance-limiting phenomena, beam-cavity interaction issues specific to superconducting cavities, approaches to designing SRF systems and engineering of superconducting cavity cryomodules. The course is intended for students interested in accelerator physics and technology who want to learn about application of RF superconductivity to particle accelerators.

Course Content

The course will include a brief introduction of the basic concepts of microwave cavities and fundamental 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 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 SRF systems for accelerators. We discuss the ways in which the superconducting material, and in particular the surface, can be modified to improve quality factor and accelerating gradient. Finally, we will address issues related to engineering of the SRF system components: cryostats, cavities, input couplers, HOM loads, and frequency tuners.

Learning Goals

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

Main Texts and suggested materials

While all necessary material will be provided during lectures, we recommend the following textbook for in-depth study of the subject:

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

Other Reading Recommendations 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)
• Classical Electrodynamics (Chapters 1 through 8) by J. D. Jackson, John Wiley & Sons, 3rd edition (1999)

or other similar textbooks. Additional reference books:

• Handbook of Accelerator Physics and Engineering, edited by A. W. Chao, K. H. Mess, M. Tigner, and F. Zimmermann, World Scientific, 2nd Edition (2013)
• RF Superconductivity: Science, Technology, and Applications, by H. Padamsee, Wiley-VCH (2009)

Online resources:

• The Physics of Electron Storage Rings: An Introduction, by M. Sands
• Microwave Theory and Applications, by S. F. Adam
• High Energy Electron Linacs: Applications to Storage Ring RF Systems and Linear Colliders, by Perry B. Wilson

Grades

Students will be evaluated based on the following performance criteria: final exam (50%), homework assignments and class participation (50%). Credits earned upon successful completion of this course can be applied toward receiving a Certificate in Accelerator Science and Engineering under the Ernest Courant Traineeship in Accelerator Science & Engineering.

Lecture Notes

• [ Lecture 1: Introduction], by Prof. Belomestnykh
• [ Lecture 2: Brief survey of particle accelerators], by Dr. Posen
• [ Lecture 3: RF fundamentals, part 1], by Prof. Belomestnykh
• [ Lecture 4: RF fundamentals, part 2], by Prof. Belomestnykh
• [ Lecture 5: SRF fundamentals, part 1], by Dr. Posen
• [ Lecture 6: SRF fundamentals, part 2], by Dr. Posen
• [ Lecture 7: Cavity performance frontier], by Dr. Posen
• [ Lecture 8: Related phenomena], by Dr. Petrushina
• [ Lecture 9: SRF system requirements], by Dr. Posen
• [ Lecture 10: Beam-cavity interactions], by Prof. Belomestnykh
• [ Lecture 11-12: Systems engineering, parts 1 and 2], by Dr. Posen
• [ Lecture 13: Cavity design], by Dr. Petrushina
• [ Lecture 14: Cryomodule design], by Dr. Posen
• [ Lecture 15: Fundamental power couplers], by Prof. Belomestnykh
• [ Lecture 16: HOM dampers], by Prof. Belomestnykh
• [ Lecture 17: Cavity frequency tuners], by Prof. Belomestnykh
• [ Lecture 18: Cavity fabrication and processing], by Dr. Posen
• [ Lecture 19: SRF cavity testing and instrumentation], by Prof. Belomestnykh
• [ Lecture 20: High power RF sources], by Prof. Belomestnykh
• [ Lecture 21: Case study: LCLS-II], by Prof. Belomestnykh
• [ Lecture 22-23: Refrigerationand cryogenics. Low temperature material properties and heat transfer], by Mr. Klebaner
• [ Lecture 24: SRF in quantum regime], by Dr. Posen
• [ Lecture 25: Overview of remaining SRF challenges], by Prof. Belomestnykh

Homeworks

• HW1 Due February 6
• HW2 Due February 27
• HW3 Due March 27
• HW4 Due April 17

Homework review sessions

• Session 1, February 13
• Session 2, March 6
• Session 3, April 3
• Session 4, April 24

Final Exam due May 10